Ranging assisted pedestrian localization

ABSTRACT

Disclosed are techniques for wireless communication. In an aspect, a method of wireless communication performed by a first pedestrian user equipment (PUE) includes performing a ranging operation to a set of UEs, the set including at least a second PUE, and providing ranging data to a third entity, the third entity comprising a vehicle user equipment (VUE) or a road-side unit (RSU). The set of UEs may be randomly selected or selected using a selection algorithm. The set of UEs may be selected by the PUE or by the third entity. The ranging data may include the location of the first PUE, and may include a report on the battery status of the first PUE. The third entity may use the ranging data to update estimated positions of the first PUE and the set of UEs.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application for patent is a Divisional of U.S.Non-Provisional application Ser. No. 17/206,062, entitled “RANGINGASSISTED PEDESTRIAN LOCALIZATION,” filed Mar. 18, 2021, which isassigned to the assignee hereof, and which is expressly incorporatedherein by reference in its entirety.

BACKGROUND OF THE DISCLOSURE 1. Field of the Disclosure

Aspects of the disclosure relate generally to wireless communications.

2. Description of the Related Art

Wireless communication systems have developed through variousgenerations, including a first-generation analog wireless phone service(1G), a second-generation (2G) digital wireless phone service (includinginterim 2.5G and 2.75G networks), a third-generation (3G) high speeddata, Internet-capable wireless service and a fourth-generation (4G)service (e.g., Long Term Evolution (LTE) or WiMax). There are presentlymany different types of wireless communication systems in use, includingcellular and personal communications service (PCS) systems. Examples ofknown cellular systems include the cellular analog advanced mobile phonesystem (AMPS), and digital cellular systems based on code divisionmultiple access (CDMA), frequency division multiple access (FDMA), timedivision multiple access (TDMA), the Global System for Mobilecommunications (GSM), etc.

A fifth generation (5G) wireless standard, referred to as New Radio(NR), calls for higher data transfer speeds, greater numbers ofconnections, and better coverage, among other improvements. The 5Gstandard, according to the Next Generation Mobile Networks Alliance, isdesigned to provide data rates of several tens of megabits per second toeach of tens of thousands of users, with 1 gigabit per second to tens ofworkers on an office floor. Several hundreds of thousands ofsimultaneous connections should be supported in order to support largesensor deployments. Consequently, the spectral efficiency of 5G mobilecommunications should be significantly enhanced compared to the current4G standard. Furthermore, signaling efficiencies should be enhanced andlatency should be substantially reduced compared to current standards.

Leveraging the increased data rates and decreased latency of 5G, amongother things, vehicle-to-everything (V2X) communication technologies arebeing implemented to support autonomous driving applications, such aswireless communications between vehicles, between vehicles and theroadside infrastructure, between vehicles and pedestrians, etc.

SUMMARY

The following presents a simplified summary relating to one or moreaspects disclosed herein. Thus, the following summary should not beconsidered an extensive overview relating to all contemplated aspects,nor should the following summary be considered to identify key orcritical elements relating to all contemplated aspects or to delineatethe scope associated with any particular aspect. Accordingly, thefollowing summary has the sole purpose to present certain conceptsrelating to one or more aspects relating to the mechanisms disclosedherein in a simplified form to precede the detailed descriptionpresented below.

In an aspect, a pedestrian user equipment (PUE) includes a memory; atleast one transceiver; and at least one processor communicativelycoupled to the memory and the at least one transceiver, the at least oneprocessor configured to: perform a ranging operation to a set of userequipment (UEs), the set comprising at least a second PUE; and provideranging data to a third entity, the third entity comprising a vehicleuser equipment (VUE) or a road-side unit (RSU).

In an aspect, a vehicle user equipment (VUE) includes a memory; at leastone transceiver; and at least one processor communicatively coupled tothe memory and the at least one transceiver, the at least one processorconfigured to: send, to a first pedestrian user equipment (PUE), arequest to perform a ranging operation to a set of user equipment (UEs),the set comprising at least a second PUE; receive, from the first PUE,ranging data indicating a range from the first PUE to each member of theset of UEs; and determine, based on the ranging data, an estimatedposition for each UE in the set of UEs.

In an aspect, a road-side unit (RSU) includes a memory; at least onetransceiver; and at least one processor communicatively coupled to thememory and the at least one transceiver, the at least one processorconfigured to: send, to a first pedestrian user equipment (PUE), arequest to perform a ranging operation to a set of user equipment (UEs),the set comprising at least a second PUE; receive, from the first PUE,ranging data indicating a range from the first PUE to each member of theset of UEs; and send, to a vehicle UE (VUE), the ranging data, anestimated position of each member of the set of UEs, or combinationsthereof.

In an aspect, a method of wireless communication performed by a firstuser equipment (UE) includes sending, to a second UE, a request toperform a ranging operation to a set of user equipment (UEs), the setcomprising at least a pedestrian UE (PUE); receiving, from the secondUE, ranging data indicating a range from the second UE to each member ofthe set of UEs; and determining, based on the ranging data, an estimatedposition for each UE in the set of UEs.

Other objects and advantages associated with the aspects disclosedherein will be apparent to those skilled in the art based on theaccompanying drawings and detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are presented to aid in the description ofvarious aspects of the disclosure and are provided solely forillustration of the aspects and not limitation thereof.

FIG. 1 illustrates an example wireless communications system, accordingto aspects of the disclosure.

FIGS. 2A and 2B illustrate example wireless network structures,according to aspects of the disclosure.

FIG. 3 illustrates an example of a wireless communications system thatsupports unicast sidelink establishment, according to aspects of thedisclosure.

FIG. 4A is a block diagram illustrating various components of an exampleuser equipment (UE), according to aspects of the disclosure.

FIG. 4B is a block diagram illustrating various components of an exampleroad-side unit (RSU), according to aspects of the disclosure.

FIGS. 5 to 8 illustrate conventional methods of pedestrian localization.

FIGS. 9 to 17 illustrate methods for ranging-assisted pedestrianlocalization according to aspects of the disclosure.

DETAILED DESCRIPTION

Aspects of the disclosure are provided in the following description andrelated drawings directed to various examples provided for illustrationpurposes. Alternate aspects may be devised without departing from thescope of the disclosure. Additionally, well-known elements of thedisclosure will not be described in detail or will be omitted so as notto obscure the relevant details of the disclosure.

The words “exemplary” and/or “example” are used herein to mean “servingas an example, instance, or illustration.” Any aspect described hereinas “exemplary” and/or “example” is not necessarily to be construed aspreferred or advantageous over other aspects. Likewise, the term“aspects of the disclosure” does not require that all aspects of thedisclosure include the discussed feature, advantage, or mode ofoperation.

Those of skill in the art will appreciate that the information andsignals described below may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the description below may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof, depending inpart on the particular application, in part on the desired design, inpart on the corresponding technology, etc.

Further, many aspects are described in terms of sequences of actions tobe performed by, for example, elements of a computing device. It will berecognized that various actions described herein can be performed byspecific circuits (e.g., application specific integrated circuits(ASICs)), by program instructions being executed by one or moreprocessors, or by a combination of both. Additionally, the sequence(s)of actions described herein can be considered to be embodied entirelywithin any form of non-transitory computer-readable storage mediumhaving stored therein a corresponding set of computer instructions that,upon execution, would cause or instruct an associated processor of adevice to perform the functionality described herein. Thus, the variousaspects of the disclosure may be embodied in a number of differentforms, all of which have been contemplated to be within the scope of theclaimed subject matter. In addition, for each of the aspects describedherein, the corresponding form of any such aspects may be describedherein as, for example, “logic configured to” perform the describedaction.

A “vulnerable road user” (VRU) is a term applied to those most at riskin traffic, i.e. those unprotected by an outside shield. Pedestrians,pedal cyclists, and motor cyclists are accordingly considered asvulnerable since they benefit from little or no external protectivedevices that would absorb energy in a collision. VRUs includenon-motorized road users, such as pedestrians and cyclists as well asmotor-cyclists and persons with disabilities or reduced mobility andorientation.

A “vehicle UE” (VUE) is a type of UE and may be any in-vehicle wirelesscommunication device, such as a navigation system, a warning system, aheads-up display (HUD), an on-board computer, etc. Alternatively, a VUEmay be a portable wireless communication device (e.g., a cell phone,tablet computer, etc.) that is carried by the driver of the vehicle or apassenger in the vehicle. The term “VUE” may refer to the in-vehiclewireless communication device or the vehicle itself, depending on thecontext.

A “pedestrian UE” (PUE) is a type of UE and may be a portable wirelesscommunication device that is carried by a pedestrian (i.e., a user thatis not driving or riding in a vehicle). Generally, UEs can communicatewith a core network via a RAN, and through the core network the UEs canbe connected with external networks such as the Internet and with otherUEs. Of course, other mechanisms of connecting to the core networkand/or the Internet are also possible for the UEs, such as over wiredaccess networks, wireless local area network (WLAN) networks (e.g.,based on IEEE 802.11, etc.) and so on.

A “road-side unit” (RSU) is a computing device located on the roadsidethat provides connectivity support to passing vehicles (e.g., VUEs),PUEs, and other types of UEs in the vicinity, e.g., supporting vehicleto infrastructure (V2I) communications.

As used herein, the terms UE, VUE, PUE, RSU, and “base station” are notintended to be specific or otherwise limited to any particular radioaccess technology (RAT), unless otherwise noted. In general, a UE may beany wireless communication device (e.g., vehicle on-board computer,vehicle navigation device, mobile phone, router, tablet computer, laptopcomputer, tracking device, wearable (e.g., smartwatch, glasses,augmented reality (AR)/virtual reality (VR) headset, etc.), vehicle(e.g., automobile, motorcycle, bicycle, etc.), Internet of Things (IoT)device, etc.) used by a user to communicate over a wirelesscommunications network. A UE may be mobile or may (e.g., at certaintimes) be stationary, and may communicate with a radio access network(RAN). As used herein, the term “UE” may be referred to interchangeablyas a “mobile device,” an “access terminal” or “AT,” a “client device,” a“wireless device,” a “subscriber device,” a “subscriber terminal,” a“subscriber station,” a “user terminal” or UT, a “mobile terminal,” a“mobile station,” or variations thereof.

A base station may operate according to one of several RATs incommunication with UEs depending on the network in which it is deployed,and may be alternatively referred to as an access point (AP), a networknode, a NodeB, an evolved NodeB (eNB), a next generation eNB (ng-eNB), aNew Radio (NR) Node B (also referred to as a gNB or gNodeB), etc. A basestation may be used primarily to support wireless access by UEsincluding supporting data, voice and/or signaling connections for thesupported UEs. In some systems a base station may provide purely edgenode signaling functions while in other systems it may provideadditional control and/or network management functions. A communicationlink through which UEs can send signals to a base station is called anuplink (UL) channel (e.g., a reverse traffic channel, a reverse controlchannel, an access channel, etc.). A communication link through whichthe base station can send signals to UEs is called a downlink (DL) orforward link channel (e.g., a paging channel, a control channel, abroadcast channel, a forward traffic channel, etc.). As used herein theterm traffic channel (TCH) can refer to either an UL/reverse orDL/forward traffic channel.

The term “base station” may refer to a single physicaltransmission-reception point (TRP) or to multiple physical TRPs that mayor may not be co-located. For example, where the term “base station”refers to a single physical TRP, the physical TRP may be an antenna ofthe base station corresponding to a cell (or several cell sectors) ofthe base station. Where the term “base station” refers to multipleco-located physical TRPs, the physical TRPs may be an array of antennas(e.g., as in a multiple-input multiple-output (MIMO) system or where thebase station employs beamforming) of the base station. Where the term“base station” refers to multiple non-co-located physical TRPs, thephysical TRPs may be a distributed antenna system (DAS) (a network ofspatially separated antennas connected to a common source via atransport medium) or a remote radio head (RRH) (a remote base stationconnected to a serving base station). Alternatively, the non-co-locatedphysical TRPs may be the serving base station receiving the measurementreport from the UE and a neighbor base station whose reference radiofrequency (RF) signals the UE is measuring. Because a TRP is the pointfrom which a base station transmits and receives wireless signals, asused herein, references to transmission from or reception at a basestation are to be understood as referring to a particular TRP of thebase station.

In some aspects that support positioning of UEs, a base station may notsupport wireless access by UEs (e.g., may not support data, voice,and/or signaling connections for UEs), but may instead transmitreference RF signals to UEs to be measured by the UEs and/or may receiveand measure signals transmitted by the UEs. Such base stations may bereferred to as positioning beacons (e.g., when transmitting RF signalsto UEs) and/or as location measurement units (e.g., when receiving andmeasuring RF signals from UEs).

An “RF signal” comprises an electromagnetic wave of a given frequencythat transports information through the space between a transmitter anda receiver. As used herein, a transmitter may transmit a single “RFsignal” or multiple “RF signals” to a receiver. However, the receivermay receive multiple “RF signals” corresponding to each transmitted RFsignal due to the propagation characteristics of RF signals throughmultipath channels. The same transmitted RF signal on different pathsbetween the transmitter and receiver may be referred to as a “multipath”RF signal. As used herein, an RF signal may also be referred to as a“wireless signal” or simply a “signal” where it is clear from thecontext that the term “signal” refers to a wireless signal or an RFsignal.

FIG. 1 illustrates an example wireless communications system 100. Thewireless communications system 100 (which may also be referred to as awireless wide area network (WWAN)) may include various base stations 102(labelled “BS”) and various UEs 104. The base stations 102 may includemacro cell base stations (high power cellular base stations) and/orsmall cell base stations (low power cellular base stations). In anaspect, the macro cell base stations 102 may include eNBs and/or ng-eNBswhere the wireless communications system 100 corresponds to an LTEnetwork, or gNBs where the wireless communications system 100corresponds to a NR network, or a combination of both, and the smallcell base stations may include femtocells, picocells, microcells, etc.

The base stations 102 may collectively form a RAN and interface with acore network 174 (e.g., an evolved packet core (EPC) or 5G core (5GC))through backhaul links 122, and through the core network 174 to one ormore location servers 172 (which may be part of core network 174 or maybe external to core network 174). In addition to other functions, thebase stations 102 may perform functions that relate to one or more oftransferring user data, radio channel ciphering and deciphering,integrity protection, header compression, mobility control functions(e.g., handover, dual connectivity), inter-cell interferencecoordination, connection setup and release, load balancing, distributionfor non-access stratum (NAS) messages, NAS node selection,synchronization, RAN sharing, multimedia broadcast multicast service(MBMS), subscriber and equipment trace, RAN information management(RIM), paging, positioning, and delivery of warning messages. The basestations 102 may communicate with each other directly or indirectly(e.g., through the EPC/5GC) over backhaul links 134, which may be wiredor wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Eachof the base stations 102 may provide communication coverage for arespective geographic coverage area 110. In an aspect, one or more cellsmay be supported by a base station 102 in each geographic coverage area110. A “cell” is a logical communication entity used for communicationwith a base station (e.g., over some frequency resource, referred to asa carrier frequency, component carrier, carrier, band, or the like), andmay be associated with an identifier (e.g., a physical cell identifier(PCI), an enhanced cell identifier (ECI), a virtual cell identifier(VCI), a cell global identifier (CGI), etc.) for distinguishing cellsoperating via the same or a different carrier frequency. In some cases,different cells may be configured according to different protocol types(e.g., machine-type communication (MTC), narrowband IoT (NB-IoT),enhanced mobile broadband (eMBB), or others) that may provide access fordifferent types of UEs. Because a cell is supported by a specific basestation, the term “cell” may refer to either or both the logicalcommunication entity and the base station that supports it, depending onthe context. In some cases, the term “cell” may also refer to ageographic coverage area of a base station (e.g., a sector), insofar asa carrier frequency can be detected and used for communication withinsome portion of geographic coverage areas 110.

While neighboring macro cell base station 102 geographic coverage areas110 may partially overlap (e.g., in a handover region), some of thegeographic coverage areas 110 may be substantially overlapped by alarger geographic coverage area 110. For example, a small cell basestation 102′ (labelled “SC” for “small cell”) may have a geographiccoverage area 110′ that substantially overlaps with the geographiccoverage area 110 of one or more macro cell base stations 102. A networkthat includes both small cell and macro cell base stations may be knownas a heterogeneous network. A heterogeneous network may also includehome eNBs (HeNBs), which may provide service to a restricted group knownas a closed subscriber group (CSG).

The communication links 120 between the base stations 102 and the UEs104 may include uplink (also referred to as reverse link) transmissionsfrom a UE 104 to a base station 102 and/or downlink (DL) (also referredto as forward link) transmissions from a base station 102 to a UE 104.The communication links 120 may use MIMO antenna technology, includingspatial multiplexing, beamforming, and/or transmit diversity. Thecommunication links 120 may be through one or more carrier frequencies.Allocation of carriers may be asymmetric with respect to downlink anduplink (e.g., more or less carriers may be allocated for downlink thanfor uplink).

The wireless communications system 100 may further include a wirelesslocal area network (WLAN) access point (AP) 150 in communication withWLAN stations (STAs) 152 via communication links 154 in an unlicensedfrequency spectrum (e.g., 5 GHz). When communicating in an unlicensedfrequency spectrum, the WLAN STAs 152 and/or the WLAN AP 150 may performa clear channel assessment (CCA) or listen before talk (LBT) procedureprior to communicating in order to determine whether the channel isavailable.

The small cell base station 102′ may operate in a licensed and/or anunlicensed frequency spectrum. When operating in an unlicensed frequencyspectrum, the small cell base station 102′ may employ LTE or NRtechnology and use the same 5 GHz unlicensed frequency spectrum as usedby the WLAN AP 150. The small cell base station 102′, employing LTE/5Gin an unlicensed frequency spectrum, may boost coverage to and/orincrease capacity of the access network. NR in unlicensed spectrum maybe referred to as NR-U. LTE in an unlicensed spectrum may be referred toas LTE-U, licensed assisted access (LAA), or MulteFire.

The wireless communications system 100 may further include a mmW basestation 180 that may operate in mmW frequencies and/or near mmWfrequencies in communication with a UE 182. Extremely high frequency(EHF) is part of the RF in the electromagnetic spectrum. EHF has a rangeof 30 GHz to 300 GHz and a wavelength between 1 millimeter and 10millimeters. Radio waves in this band may be referred to as a millimeterwave. Near mmW may extend down to a frequency of 3 GHz with a wavelengthof 100 millimeters. The super high frequency (SHF) band extends between3 GHz and 30 GHz, also referred to as centimeter wave. Communicationsusing the mmW/near mmW radio frequency band have high path loss and arelatively short range. The mmW base station 180 and the UE 182 mayutilize beamforming (transmit and/or receive) over a mmW communicationlink 184 to compensate for the extremely high path loss and short range.Further, it will be appreciated that in alternative configurations, oneor more base stations 102 may also transmit using mmW or near mmW andbeamforming. Accordingly, it will be appreciated that the foregoingillustrations are merely examples and should not be construed to limitthe various aspects disclosed herein.

Transmit beamforming is a technique for focusing an RF signal in aspecific direction. Traditionally, when a network node (e.g., a basestation) broadcasts an RF signal, it broadcasts the signal in alldirections (omni-directionally). With transmit beamforming, the networknode determines where a given target device (e.g., a UE) is located(relative to the transmitting network node) and projects a strongerdownlink RF signal in that specific direction, thereby providing afaster (in terms of data rate) and stronger RF signal for the receivingdevice(s). To change the directionality of the RF signal whentransmitting, a network node can control the phase and relativeamplitude of the RF signal at each of the one or more transmitters thatare broadcasting the RF signal. For example, a network node may use anarray of antennas (referred to as a “phased array” or an “antennaarray”) that creates a beam of RF waves that can be “steered” to pointin different directions, without actually moving the antennas.Specifically, the RF current from the transmitter is fed to theindividual antennas with the correct phase relationship so that theradio waves from the separate antennas add together to increase theradiation in a desired direction, while cancelling to suppress radiationin undesired directions.

Transmit beams may be quasi-collocated, meaning that they appear to thereceiver (e.g., a UE) as having the same parameters, regardless ofwhether or not the transmitting antennas of the network node themselvesare physically collocated. In NR, there are four types ofquasi-co-location (QCL) relations. Specifically, a QCL relation of agiven type means that certain parameters about a second reference RFsignal on a second beam can be derived from information about a sourcereference RF signal on a source beam. Thus, if the source reference RFsignal is QCL Type A, the receiver can use the source reference RFsignal to estimate the Doppler shift, Doppler spread, average delay, anddelay spread of a second reference RF signal transmitted on the samechannel. If the source reference RF signal is QCL Type B, the receivercan use the source reference RF signal to estimate the Doppler shift andDoppler spread of a second reference RF signal transmitted on the samechannel. If the source reference RF signal is QCL Type C, the receivercan use the source reference RF signal to estimate the Doppler shift andaverage delay of a second reference RF signal transmitted on the samechannel. If the source reference RF signal is QCL Type D, the receivercan use the source reference RF signal to estimate the spatial receiveparameter of a second reference RF signal transmitted on the samechannel.

In receive beamforming, the receiver uses a receive beam to amplify RFsignals detected on a given channel. For example, the receiver canincrease the gain setting and/or adjust the phase setting of an array ofantennas in a particular direction to amplify (e.g., to increase thegain level of) the RF signals received from that direction. Thus, when areceiver is said to beamform in a certain direction, it means the beamgain in that direction is high relative to the beam gain along otherdirections, or the beam gain in that direction is the highest comparedto the beam gain in that direction of all other receive beams availableto the receiver. This results in a stronger received signal strength(e.g., reference signal received power (RSRP), reference signal receivedquality (RSRQ), signal-to-interference-plus-noise ratio (SINR), etc.) ofthe RF signals received from that direction.

Transmit and receive beams may be spatially related. A spatial relationmeans that parameters for a second beam (e.g., a transmit or receivebeam) for a second reference signal can be derived from informationabout a first beam (e.g., a receive beam or a transmit beam) for a firstreference signal. For example, a UE may use a particular receive beam toreceive a reference downlink reference signal (e.g., synchronizationsignal block (SSB)) from a base station. The UE can then form a transmitbeam for sending an uplink reference signal (e.g., sounding referencesignal (SRS)) to that base station based on the parameters of thereceive beam.

Note that a “downlink” beam may be either a transmit beam or a receivebeam, depending on the entity forming it. For example, if a base stationis forming the downlink beam to transmit a reference signal to a UE, thedownlink beam is a transmit beam. If the UE is forming the downlinkbeam, however, it is a receive beam to receive the downlink referencesignal. Similarly, an “uplink” beam may be either a transmit beam or areceive beam, depending on the entity forming it. For example, if a basestation is forming the uplink beam, it is an uplink receive beam, and ifa UE is forming the uplink beam, it is an uplink transmit beam.

In 5G, the frequency spectrum in which wireless nodes (e.g., basestations 102/180, UEs 104/182) operate is divided into multiplefrequency ranges, FR1 (from 450 to 6000 MHz), FR2 (from 24250 to 52600MHz), FR3 (above 52600 MHz), and FR4 (between FR1 and FR2). mmWfrequency bands generally include the FR2, FR3, and FR4 frequencyranges. As such, the terms “mmW” and “FR2” or “FR3” or “FR4” maygenerally be used interchangeably.

In a multi-carrier system, such as 5G, one of the carrier frequencies isreferred to as the “primary carrier” or “anchor carrier” or “primaryserving cell” or “PCell,” and the remaining carrier frequencies arereferred to as “secondary carriers” or “secondary serving cells” or“SCells.” In carrier aggregation, the anchor carrier is the carrieroperating on the primary frequency (e.g., FR1) utilized by a UE 104/182and the cell in which the UE 104/182 either performs the initial radioresource control (RRC) connection establishment procedure or initiatesthe RRC connection re-establishment procedure. The primary carriercarries all common and UE-specific control channels, and may be acarrier in a licensed frequency (however, this is not always the case).A secondary carrier is a carrier operating on a second frequency (e.g.,FR2) that may be configured once the RRC connection is establishedbetween the UE 104 and the anchor carrier and that may be used toprovide additional radio resources. In some cases, the secondary carriermay be a carrier in an unlicensed frequency. The secondary carrier maycontain only necessary signaling information and signals, for example,those that are UE-specific may not be present in the secondary carrier,since both primary uplink and downlink carriers are typicallyUE-specific. This means that different UEs 104/182 in a cell may havedifferent downlink primary carriers. The same is true for the uplinkprimary carriers. The network is able to change the primary carrier ofany UE 104/182 at any time. This is done, for example, to balance theload on different carriers. Because a “serving cell” (whether a PCell oran SCell) corresponds to a carrier frequency/component carrier overwhich some base station is communicating, the term “cell,” “servingcell,” “component carrier,” “carrier frequency,” and the like can beused interchangeably.

For example, still referring to FIG. 1 , one of the frequencies utilizedby the macro cell base stations 102 may be an anchor carrier (or“PCell”) and other frequencies utilized by the macro cell base stations102 and/or the mmW base station 180 may be secondary carriers(“SCells”). The simultaneous transmission and/or reception of multiplecarriers enables the UE 104/182 to significantly increase its datatransmission and/or reception rates. For example, two 20 MHz aggregatedcarriers in a multi-carrier system would theoretically lead to atwo-fold increase in data rate (i.e., 40 MHz), compared to that attainedby a single 20 MHz carrier.

In the example of FIG. 1 , one or more Earth orbiting satellitepositioning system (SPS) space vehicles (SVs) 112 (e.g., satellites) maybe used as an independent source of location information for any of theillustrated UEs (shown in FIG. 1 as a single UE 104 for simplicity). AUE 104 may include one or more dedicated SPS receivers specificallydesigned to receive signals for deriving geo location information fromthe SVs 112. An SPS typically includes a system of transmitters (e.g.,SVs 112) positioned to enable receivers (e.g., UEs 104) to determinetheir location on or above the Earth based, at least in part, on signalsreceived from the transmitters. Such a transmitter typically transmits asignal 124 marked with a repeating pseudo-random noise (PN) code of aset number of chips. While typically located in SVs 112, transmittersmay sometimes be located on ground-based control stations, base stations102, and/or other UEs 104.

The use of SPS signals can be augmented by various satellite-basedaugmentation systems (SBAS) that may be associated with or otherwiseenabled for use with one or more global and/or regional navigationsatellite systems. For example an SBAS may include an augmentationsystem(s) that provides integrity information, differential corrections,etc., such as the Wide Area Augmentation System (WAAS), the EuropeanGeostationary Navigation Overlay Service (EGNOS), the Multi-functionalSatellite Augmentation System (MSAS), the Global Positioning System(GPS) Aided Geo Augmented Navigation or GPS and Geo Augmented Navigationsystem (GAGAN), and/or the like. Thus, as used herein, an SPS mayinclude any combination of one or more global and/or regional navigationsatellite systems and/or augmentation systems, and SPS signals mayinclude SPS, SPS-like, and/or other signals associated with such one ormore SPS.

Leveraging the increased data rates and decreased latency of NR, amongother things, vehicle-to-everything (V2X) communication technologies arebeing implemented to support intelligent transportation systems (ITS)applications, such as wireless communications between vehicles(vehicle-to-vehicle (V2V)), between vehicles and the roadsideinfrastructure (vehicle-to-infrastructure (V2I)), and between vehiclesand pedestrians (vehicle-to-pedestrian (V2P)). The goal is for vehiclesto be able to sense the environment around them and communicate thatinformation to other vehicles, infrastructure, and personal mobiledevices. Such vehicle communication will enable safety, mobility, andenvironmental advancements that current technologies are unable toprovide. Once fully implemented, the technology is expected to reduceunimpaired vehicle crashes by 80%.

Still referring to FIG. 1 , the wireless communications system 100 mayinclude multiple VUEs 160 that may communicate with base stations 102over communication links 120 (e.g., using the UVU interface). VUEs 160may also communicate directly with each other over a wireless sidelink162, with a roadside access point 164 (also referred to as a “roadsideunit”) over a wireless sidelink 166, or with UEs 104 over a wirelesssidelink 168. A wireless sidelink (or just “sidelink”) is an adaptationof the core cellular (e.g., LTE, NR) standard that allows directcommunication between two or more UEs without the communication needingto go through a base station. Sidelink communication may be unicast ormulticast, and may be used for D2D media-sharing, V2V communication, V2Xcommunication (e.g., cellular V2X (cV2X) communication, enhanced V2X(eV2X) communication, etc.), emergency rescue applications, etc. One ormore of a group of VUEs 160 utilizing sidelink communications may bewithin the geographic coverage area 110 of a base station 102. OtherVUEs 160 in such a group may be outside the geographic coverage area 110of a base station 102 or be otherwise unable to receive transmissionsfrom a base station 102. In some cases, groups of VUEs 160 communicatingvia sidelink communications may utilize a one-to-many (1:M) system inwhich each VUE 160 transmits to every other VUE 160 in the group. Insome cases, a base station 102 facilitates the scheduling of resourcesfor sidelink communications. In other cases, sidelink communications arecarried out between VUEs 160 without the involvement of a base station102.

In an aspect, the sidelinks 162, 166, 168 may operate over a wirelesscommunication medium of interest, which may be shared with otherwireless communications between other vehicles and/or infrastructureaccess points, as well as other RATs. A “medium” may be composed of oneor more time, frequency, and/or space communication resources (e.g.,encompassing one or more channels across one or more carriers)associated with wireless communication between one or moretransmitter/receiver pairs.

In an aspect, the sidelinks 162, 166, 168 may be cV2X links. A firstgeneration of cV2X has been standardized in LTE, and the next generationis expected to be defined in NR. cV2X is a cellular technology that alsoenables device-to-device communications. In the U.S. and Europe, cV2X isexpected to operate in the licensed ITS band in sub-6 GHz. Other bandsmay be allocated in other countries. Thus, as a particular example, themedium of interest utilized by sidelinks 162, 166, 168 may correspond toat least a portion of the licensed ITS frequency band of sub-6 GHz.However, the present disclosure is not limited to this frequency band orcellular technology.

In an aspect, the sidelinks 162, 166, 168 may be dedicated short-rangecommunications (DSRC) links. DSRC is a one-way or two-way short-range tomedium-range wireless communication protocol that uses the wirelessaccess for vehicular environments (WAVE) protocol, also known as IEEE802.11p, for V2V, V2I, and V2P communications. IEEE 802.11p is anapproved amendment to the IEEE 802.11 standard and operates in thelicensed ITS band of 5.9 GHz (5.85-5.925 GHz) in the U.S. In Europe,IEEE 802.11p operates in the ITS GSA band (5.875-5.905 MHz). Other bandsmay be allocated in other countries. The V2V communications brieflydescribed above occur on the Safety Channel, which in the U.S. istypically a 10 MHz channel that is dedicated to the purpose of safety.The remainder of the DSRC band (the total bandwidth is 75 MHz) isintended for other services of interest to drivers, such as road rules,tolling, parking automation, etc. Thus, as a particular example, themediums of interest utilized by sidelinks 162, 166, 168 may correspondto at least a portion of the licensed ITS frequency band of 5.9 GHz.

Alternatively, the medium of interest may correspond to at least aportion of an unlicensed frequency band shared among various RATs.Although different licensed frequency bands have been reserved forcertain communication systems (e.g., by a government entity such as theFederal Communications Commission (FCC) in the United States), thesesystems, in particular those employing small cell access points, haverecently extended operation into unlicensed frequency bands such as theUnlicensed National Information Infrastructure (U-NII) band used bywireless local area network (WLAN) technologies, most notably IEEE802.11x WLAN technologies generally referred to as “Wi-Fi.” Examplesystems of this type include different variants of CDMA systems, TDMAsystems, FDMA systems, orthogonal FDMA (OFDMA) systems, single-carrierFDMA (SC-FDMA) systems, and so on.

Communications between the VUEs 160 are referred to as V2Vcommunications, communications between the VUEs 160 and the one or moreroadside access points 164 are referred to as V2I communications, andcommunications between the VUEs 160 and one or more UEs 104 (where theUEs 104 are PUEs) are referred to as V2P communications. The V2Vcommunications between VUEs 160 may include, for example, informationabout the position, speed, acceleration, heading, and other vehicle dataof the VUEs 160. The V2I information received at a VUE 160 from the oneor more roadside access points 164 may include, for example, road rules,parking automation information, etc. The V2P communications between aVUE 160 and a UE 104 may include information about, for example, theposition, speed, acceleration, and heading of the VUE 160 and theposition, speed (e.g., where the UE 104 is carried by a user on abicycle), and heading of the UE 104.

Note that although FIG. 1 only illustrates two of the UEs as VUEs (VUEs160), any of the illustrated UEs (e.g., UEs 104, 152, 182, 190) may beVUEs. In addition, while only the VUEs 160 and a single UE 104 have beenillustrated as being connected over a sidelink, any of the UEsillustrated in FIG. 1 , whether VUEs, PUEs, etc., may be capable ofsidelink communication. Further, although only UE 182 was described asbeing capable of beam forming, any of the illustrated UEs, includingVUEs 160, may be capable of beam forming. Where VUEs 160 are capable ofbeam forming, they may beam form towards each other (i.e., towards otherVUEs 160), towards roadside access points 164, towards other UEs (e.g.,UEs 104, 152, 182, 190), etc. Thus, in some cases, VUEs 160 may utilizebeamforming over sidelinks 162, 166, and 168.

The wireless communications system 100 may further include one or moreUEs, such as UE 190, that connects indirectly to one or morecommunication networks via one or more device-to-device (D2D)peer-to-peer (P2P) links. In the example of FIG. 1 , UE 190 has a D2DP2P link 192 with one of the UEs 104 connected to one of the basestations 102 (e.g., through which UE 190 may indirectly obtain cellularconnectivity) and a D2D P2P link 194 with WLAN STA 152 connected to theWLAN AP 150 (through which UE 190 may indirectly obtain WLAN-basedInternet connectivity). In an example, the D2D P2P links 192 and 194 maybe supported with any well-known D2D RAT, such as LTE Direct (LTE-D),WiFi Direct (WiFi-D), Bluetooth®, and so on. As another example, the D2DP2P links 192 and 194 may be sidelinks, as described above withreference to sidelinks 162, 166, and 168.

FIG. 2A illustrates an example wireless network structure 200. Forexample, a 5GC 210 (also referred to as a Next Generation Core (NGC))can be viewed functionally as control plane functions (C-plane) 214(e.g., UE registration, authentication, network access, gatewayselection, etc.) and user plane functions (U-plane) 212 (e.g., UEgateway function, access to data networks, IP routing, etc.), whichoperate cooperatively to form the core network. User plane interface(NG-U) 213 and control plane interface (NG-C) 215 connect the gNB 222 tothe 5GC 210 and specifically to the user plane functions 212 and controlplane functions 214, respectively. In an additional configuration, anng-eNB 224 may also be connected to the 5GC 210 via NG-C 215 to thecontrol plane functions 214 and NG-U 213 to user plane functions 212.Further, ng-eNB 224 may directly communicate with gNB 222 via a backhaulconnection 223. In some configurations, the New RAN 220 may only haveone or more gNBs 222, while other configurations include one or more ofboth ng-eNBs 224 and gNBs 222. Either (or both) gNB 222 or ng-eNB 224may communicate with UEs 204 (e.g., any of the UEs described herein). Inan aspect, two or more UEs 204 may communicate with each other over awireless sidelink 242, which may correspond to wireless sidelink 162 inFIG. 1 .

Another optional aspect may include location server 230, which may be incommunication with the 5GC 210 to provide location assistance for UEs204. The location server 230 can be implemented as a plurality ofseparate servers (e.g., physically separate servers, different softwaremodules on a single server, different software modules spread acrossmultiple physical servers, etc.), or alternately may each correspond toa single server. The location server 230 can be configured to supportone or more location services for UEs 204 that can connect to thelocation server 230 via the core network, 5GC 210, and/or via theInternet (not illustrated). Further, the location server 230 may beintegrated into a component of the core network, or alternatively may beexternal to the core network.

FIG. 2B illustrates another example wireless network structure 250. Forexample, a 5GC 260 can be viewed functionally as control planefunctions, provided by an access and mobility management function (AMF)264, and user plane functions, provided by a user plane function (UPF)262, which operate cooperatively to form the core network (i.e., 5GC260). User plane interface 263 and control plane interface 265 connectthe ng-eNB 224 to the 5GC 260 and specifically to UPF 262 and AMF 264,respectively. In an additional configuration, a gNB 222 may also beconnected to the 5GC 260 via control plane interface 265 to AMF 264 anduser plane interface 263 to UPF 262. Further, ng-eNB 224 may directlycommunicate with gNB 222 via the backhaul connection 223, with orwithout gNB direct connectivity to the 5GC 260. In some configurations,the New RAN 220 may only have one or more gNB s 222, while otherconfigurations include one or more of both ng-eNB s 224 and gNB s 222.The base stations of the New RAN 220 communicate with the AMF 264 overthe N2 interface and with the UPF 262 over the N3 interface. Either (orboth) gNB 222 or ng-eNB 224 may communicate with UEs 204 (e.g., any ofthe UEs described herein). In an aspect, two or more UEs 204 maycommunicate with each other over a sidelink 242, which may correspond tosidelink 162 in FIG. 1 .

The functions of the AMF 264 include registration management, connectionmanagement, reachability management, mobility management, lawfulinterception, transport for session management (SM) messages between theUE 204 and a session management function (SMF) 266, transparent proxyservices for routing SM messages, access authentication and accessauthorization, transport for short message service (SMS) messagesbetween the UE 204 and the short message service function (SMSF) (notshown), and security anchor functionality (SEAF). The AMF 264 alsointeracts with an authentication server function (AUSF) (not shown) andthe UE 204, and receives the intermediate key that was established as aresult of the UE 204 authentication process. In the case ofauthentication based on a UMTS (universal mobile telecommunicationssystem) subscriber identity module (USIM), the AMF 264 retrieves thesecurity material from the AUSF. The functions of the AMF 264 alsoinclude security context management (SCM). The SCM receives a key fromthe SEAF that it uses to derive access-network specific keys. Thefunctionality of the AMF 264 also includes location services managementfor regulatory services, transport for location services messagesbetween the UE 204 and a location management function (LMF) 270 whichacts as a location server 230, transport for location services messagesbetween the New RAN 220 and the LMF 270, evolved packet system (EPS)bearer identifier allocation for interworking with the EPS, and UE 204mobility event notification. In addition, the AMF 264 also supportsfunctionalities for non-third generation partnership project (3GPP)access networks.

Functions of the UPF 262 include acting as an anchor point forintra-/inter-RAT mobility (when applicable), acting as an externalprotocol data unit (PDU) session point of interconnect to a data network(not shown), providing packet routing and forwarding, packet inspection,user plane policy rule enforcement (e.g., gating, redirection, trafficsteering), lawful interception (user plane collection), traffic usagereporting, quality of service (QoS) handling for the user plane (e.g.,uplink/downlink rate enforcement, reflective QoS marking in thedownlink), uplink traffic verification (service data flow (SDF) to QoSflow mapping), transport level packet marking in the uplink anddownlink, downlink packet buffering and downlink data notificationtriggering, and sending and forwarding of one or more “end markers” tothe source RAN node. The UPF 262 may also support transfer of locationservices messages over a user plane between the UE 204 and a locationserver such as a secure user plane location (SUPL) location platform(SLP) 272.

The functions of the SMF 266 include session management, UE Internetprotocol (IP) address allocation and management, selection and controlof user plane functions, configuration of traffic steering at the UPF262 to route traffic to the proper destination, control of part ofpolicy enforcement and QoS, and downlink data notification. Theinterface over which the SMF 266 communicates with the AMF 264 isreferred to as the N11 interface.

Another optional aspect may include an LMF 270, which may be incommunication with the 5GC 260 to provide location assistance for UEs204. The LMF 270 can be implemented as a plurality of separate servers(e.g., physically separate servers, different software modules on asingle server, different software modules spread across multiplephysical servers, etc.), or alternately may each correspond to a singleserver. The LMF 270 can be configured to support one or more locationservices for UEs 204 that can connect to the LMF 270 via the corenetwork, 5GC 260, and/or via the Internet (not illustrated). The SLP 272may support similar functions to the LMF 270 but, whereas the LMF 270may communicate with the AMF 264, New RAN 220, and UEs 204 over acontrol plane (e.g., using interfaces and protocols intended to conveysignaling messages and not voice or data), the SLP 272 may communicatewith UEs 204 and external clients (not shown in FIG. 2B) over a userplane (e.g. using protocols intended to carry voice and/or data like thetransmission control protocol (TCP) and/or IP).

FIG. 3 illustrates an example of a wireless communications system 300that supports wireless unicast sidelink establishment, according toaspects of the disclosure. In some examples, wireless communicationssystem 300 may implement aspects of wireless communications systems 100,200, and 250. Wireless communications system 300 may include a first UE302 and a second UE 304, which may be examples of any of the UEsdescribed herein. As specific examples, UEs 302 and 304 may correspondto VUEs 160 in FIG. 1 , UE 190 and UE 104 in FIG. 1 connected oversidelink 192, or UEs 204 in FIGS. 2A and 2B.

In the example of FIG. 3 , the UE 302 may attempt to establish a unicastconnection over a sidelink with the UE 304, which may be a V2X sidelinkbetween the UE 302 and UE 304. As specific examples, the establishedsidelink connection may correspond to sidelinks 162 and/or 168 in FIG. 1or sidelink 242 in FIGS. 2A and 2B. The sidelink connection may beestablished in an omni-directional frequency range (e.g., FR1) and/or ammW frequency range (e.g., FR2). In some cases, the UE 302 may bereferred to as an initiating UE that initiates the sidelink connectionprocedure, and the UE 304 may be referred to as a target UE that istargeted for the sidelink connection procedure by the initiating UE.

For establishing the unicast connection, access stratum (AS) (afunctional layer in the UMTS and LTE protocol stacks between the RAN andthe UE that is responsible for transporting data over wireless links andmanaging radio resources, and which is part of Layer 2) parameters maybe configured and negotiated between the UE 302 and UE 304. For example,a transmission and reception capability matching may be negotiatedbetween the UE 302 and UE 304. Each UE may have different capabilities(e.g., transmission and reception, 64 quadrature amplitude modulation(QAM), transmission diversity, carrier aggregation (CA), supportedcommunications frequency band(s), etc.). In some cases, differentservices may be supported at the upper layers of corresponding protocolstacks for UE 302 and UE 304. Additionally, a security association maybe established between UE 302 and UE 304 for the unicast connection.Unicast traffic may benefit from security protection at a link level(e.g., integrity protection). Security requirements may differ fordifferent wireless communications systems. For example, V2X and uGusystems may have different security requirements (e.g., ulu securitydoes not include confidentiality protection). Additionally, IPconfigurations (e.g., IP versions, addresses, etc.) may be negotiatedfor the unicast connection between UE 302 and UE 304.

In some cases, UE 304 may create a service announcement (e.g., a servicecapability message) to transmit over a cellular network (e.g., cV2X) toassist the sidelink connection establishment. Conventionally, UE 302 mayidentify and locate candidates for sidelink communications based on abasic service message (BSM) broadcasted unencrypted by nearby UEs (e.g.,UE 304). The BSM may include location information, security and identityinformation, and vehicle information (e.g., speed, maneuver, size, etc.)for the corresponding UE. However, for different wireless communicationssystems (e.g., D2D or V2X communications), a discovery channel may notbe configured so that UE 302 is able to detect the BSM(s). Accordingly,the service announcement transmitted by UE 304 and other nearby UEs(e.g., a discovery signal) may be an upper layer signal and broadcasted(e.g., in an NR sidelink broadcast). In some cases, the UE 304 mayinclude one or more parameters for itself in the service announcement,including connection parameters and/or capabilities it possesses. The UE302 may then monitor for and receive the broadcasted serviceannouncement to identify potential UEs for corresponding sidelinkconnections. In some cases, the UE 302 may identify the potential UEsbased on the capabilities each UE indicates in their respective serviceannouncements.

The service announcement may include information to assist the UE 302(e.g., or any initiating UE) to identify the UE transmitting the serviceannouncement (UE 304 in the example of FIG. 3 ). For example, theservice announcement may include channel information where directcommunication requests may be sent. In some cases, the channelinformation may be RAT-specific (e.g., specific to LTE or NR) and mayinclude a resource pool within which UE 302 transmits the communicationrequest. Additionally, the service announcement may include a specificdestination address for the UE (e.g., a Layer 2 destination address) ifthe destination address is different from the current address (e.g., theaddress of the streaming provider or UE transmitting the serviceannouncement). The service announcement may also include a network ortransport layer for the UE 302 to transmit a communication request on.For example, the network layer (also referred to as “Layer 3” or “L3”)or the transport layer (also referred to as “Layer 4” or “L4”) mayindicate a port number of an application for the UE transmitting theservice announcement. In some cases, no IP addressing may be needed ifthe signaling (e.g., PC5 signaling) carries a protocol (e.g., areal-time transport protocol (RTP)) directly or gives alocally-generated random protocol. Additionally, the serviceannouncement may include a type of protocol for credential establishmentand QoS-related parameters.

After identifying a potential sidelink connection target (UE 304 in theexample of FIG. 3 ), the initiating UE (UE 302 in the example of FIG. 3) may transmit a connection request 315 to the identified target UE 304.In some cases, the connection request 315 may be a first RRC messagetransmitted by the UE 302 to request a unicast connection with the UE304 (e.g., an “RRCDirectConnectionSetupRequest” message). For example,the unicast connection may utilize the PC5 interface for the sidelink,and the connection request 315 may be an RRC connection setup requestmessage. Additionally, the UE 302 may use a sidelink signaling radiobearer 305 to transport the connection request 315.

After receiving the connection request 315, the UE 304 may determinewhether to accept or reject the connection request 315. The UE 304 maybase this determination on a transmission/reception capability, anability to accommodate the unicast connection over the sidelink, aparticular service indicated for the unicast connection, the contents tobe transmitted over the unicast connection, or a combination thereof.For example, if the UE 302 wants to use a first RAT to transmit orreceive data, but the UE 304 does not support the first RAT, then the UE304 may reject the connection request 315. Additionally oralternatively, the UE 304 may reject the connection request 315 based onbeing unable to accommodate the unicast connection over the sidelink dueto limited radio resources, a scheduling issue, etc. Accordingly, the UE304 may transmit an indication of whether the request is accepted orrejected in a connection response 320. Similar to the UE 302 and theconnection request 315, the UE 304 may use a sidelink signaling radiobearer 310 to transport the connection response 320. Additionally, theconnection response 320 may be a second RRC message transmitted by theUE 304 in response to the connection request 315 (e.g., an“RRCDirectConnectionResponse” message).

In some cases, sidelink signaling radio bearers 305 and 310 may be thesame sidelink signaling radio bearer or may be separate sidelinksignaling radio bearers. Accordingly, a radio link control (RLC) layeracknowledged mode (AM) may be used for sidelink signaling radio bearers305 and 310. A UE that supports the unicast connection may listen on alogical channel associated with the sidelink signaling radio bearers. Insome cases, the AS layer (i.e., Layer 2) may pass information directlythrough RRC signaling (e.g., control plane) instead of a V2X layer(e.g., data plane).

If the connection response 320 indicates that the UE 304 accepted theconnection request 315, the UE 302 may then transmit a connectionestablishment 325 message on the sidelink signaling radio bearer 305 toindicate that the unicast connection setup is complete. In some cases,the connection establishment 325 may be a third RRC message (e.g., an“RRCDirectConnectionSetupComplete” message). Each of the connectionrequest 315, the connection response 320, and the connectionestablishment 325 may use a basic capability when being transported fromone UE to the other UE to enable each UE to be able to receive anddecode the corresponding transmission (e.g., the RRC messages).

Additionally, identifiers may be used for each of the connection request315, the connection response 320, and the connection establishment 325.For example, the identifiers may indicate which UE 302/304 istransmitting which message and/or for which UE 302/304 the message isintended. For physical (PHY) layer channels, the RRC signaling and anysubsequent data transmissions may use the same identifier (e.g., Layer 2IDs). However, for logical channels, the identifiers may be separate forthe RRC signaling and for the data transmissions. For example, on thelogical channels, the RRC signaling and the data transmissions may betreated differently and have different acknowledgement (ACK) feedbackmessaging. In some cases, for the RRC messaging, a physical layer ACKmay be used for ensuring the corresponding messages are transmitted andreceived properly.

One or more information elements may be included in the connectionrequest 315 and/or the connection response 320 for UE 302 and/or UE 304,respectively, to enable negotiation of corresponding AS layer parametersfor the unicast connection. For example, the UE 302 and/or UE 304 mayinclude packet data convergence protocol (PDCP) parameters in acorresponding unicast connection setup message to set a PDCP context forthe unicast connection. In some cases, the PDCP context may indicatewhether or not PDCP duplication is utilized for the unicast connection.Additionally, the UE 302 and/or UE 304 may include RLC parameters whenestablishing the unicast connection to set an RLC context for theunicast connection. For example, the RLC context may indicate whether anAM (e.g., a reordering timer (t-reordering) is used) or anunacknowledged mode (UM) is used for the RLC layer of the unicastcommunications.

Additionally, the UE 302 and/or UE 304 may include medium access control(MAC) parameters to set a MAC context for the unicast connection. Insome cases, the MAC context may enable resource selection algorithms, ahybrid automatic repeat request (HARQ) feedback scheme (e.g., ACK ornegative ACK (NACK) feedback), parameters for the HARQ feedback scheme,carrier aggregation, or a combination thereof for the unicastconnection. Additionally, the UE 302 and/or UE 304 may include PHY layerparameters when establishing the unicast connection to set a PHY layercontext for the unicast connection. For example, the PHY layer contextmay indicate a transmission format (unless transmission profiles areincluded for each UE 302/304) and a radio resource configuration (e.g.,bandwidth part (BWP), numerology, etc.) for the unicast connection.These information elements may be supported for different frequencyrange configurations (e.g., FR1 and FR2).

In some cases, a security context may also be set for the unicastconnection (e.g., after the connection establishment 325 message istransmitted). Before a security association (e.g., security context) isestablished between the UE 302 and UE 304, the sidelink signaling radiobearers 305 and 310 may not be protected. After a security associationis established, the sidelink signaling radio bearers 305 and 310 may beprotected. Accordingly, the security context may enable secure datatransmissions over the unicast connection and the sidelink signalingradio bearers 305 and 310. Additionally, IP layer parameters (e.g.,link-local IPv4 or IPv6 addresses) may also be negotiated. In somecases, the IP layer parameters may be negotiated by an upper layercontrol protocol running after RRC signaling is established (e.g., theunicast connection is established). As noted above, the UE 304 may baseits decision on whether to accept or reject the connection request 315on a particular service indicated for the unicast connection and/or thecontents to be transmitted over the unicast connection (e.g., upperlayer information). The particular service and/or contents may be alsoindicated by an upper layer control protocol running after RRC signalingis established.

After the unicast connection is established, the UE 302 and UE 304 maycommunicate using the unicast connection over a sidelink 330, wheresidelink data 335 is transmitted between the two UEs 302 and 304. Thesidelink 330 may correspond to sidelinks 162 and/or 168 in FIG. 1 and/orsidelink 242 in FIGS. 2A and 2B. In some cases, the sidelink data 335may include RRC messages transmitted between the two UEs 302 and 304. Tomaintain this unicast connection on sidelink 330, UE 302 and/or UE 304may transmit a keep alive message (e.g., “RRCDirectLinkAlive” message, afourth RRC message, etc.). In some cases, the keep alive message may betriggered periodically or on-demand (e.g., event-triggered).Accordingly, the triggering and transmission of the keep alive messagemay be invoked by UE 302 or by both UE 302 and UE 304. Additionally oralternatively, a MAC control element (CE) (e.g., defined over sidelink330) may be used to monitor the status of the unicast connection onsidelink 330 and maintain the connection. When the unicast connection isno longer needed (e.g., UE 302 travels far enough away from UE 304),either UE 302 and/or UE 304 may start a release procedure to drop theunicast connection over sidelink 330. Accordingly, subsequent RRCmessages may not be transmitted between UE 302 and UE 304 on the unicastconnection.

FIG. 4A is a block diagram illustrating various components of an exampleUE 400, according to aspects of the disclosure. In an aspect, the UE 400may correspond to any of the UEs described herein, including, but notlimited to, a VUE or a PUE. As a specific example, the UE 400 may be aVUE, such as VUE 160 in FIG. 1 . For the sake of simplicity, the variousfeatures and functions illustrated in the block diagram of FIG. 4A areconnected together using a common data bus that is meant to representthat these various features and functions are operatively coupledtogether. Those skilled in the art will recognize that otherconnections, mechanisms, features, functions, or the like, may beprovided and adapted as necessary to operatively couple and configure anactual UE. Further, it is also recognized that one or more of thefeatures or functions illustrated in the example of FIG. 4A may befurther subdivided, or two or more of the features or functionsillustrated in FIG. 4A may be combined.

The UE 400 may include at least one transceiver 404 connected to one ormore antennas 402 and providing means for communicating (e.g., means fortransmitting, means for receiving, means for measuring, means fortuning, means for refraining from transmitting, etc.) with other networknodes, such as VUEs (e.g., VUEs 160), infrastructure access points(e.g., roadside access point 164, which may also be referred to hereinas a road-side unit (RSU)), PUEs (e.g., UEs 104), base stations (e.g.,base stations 102), etc., via at least one designated RAT (e.g., cV2X orIEEE 802.11p) over one or more communication links (e.g., communicationlinks 120, sidelinks 162, 166, 168, mmW communication link 184). Thetransceiver 404 may be variously configured for transmitting andencoding signals (e.g., messages, indications, information, and so on),and, conversely, for receiving and decoding signals (e.g., messages,indications, information, pilots, and so on) in accordance with thedesignated RAT.

As used herein, a “transceiver” may include at least one transmitter andat least one receiver in an integrated device (e.g., embodied as atransmitter circuit and a receiver circuit of a single communicationdevice) in some aspects, may comprise a separate transmitter device anda separate receiver device in some aspects, or may be embodied in otherways in other aspects. In an aspect, a transmitter may include or becoupled to a plurality of antennas (e.g., antenna(s) 402), such as anantenna array, that permits the UE 400 to perform transmit“beamforming,” as described herein. Similarly, a receiver may include orbe coupled to a plurality of antennas (e.g., antenna(s) 402), such as anantenna array, that permits the UE 400 to perform receive beamforming,as described herein. In an aspect, the transmitter(s) and receiver(s)may share the same plurality of antennas (e.g., antenna(s) 402), suchthat the UE 400 can only receive or transmit at a given time, not bothat the same time. In some cases, a transceiver may not provide bothtransmit and receive functionalities. For example, a low functionalityreceiver circuit may be employed in some designs to reduce costs whenproviding full communication is not necessary (e.g., a receiver chip orsimilar circuitry simply providing low-level sniffing).

The UE 400 may also include a satellite positioning service (SPS)receiver 406. The SPS receiver 406 may be connected to the one or moreantennas 402 and may provide means for receiving and/or measuringsatellite signals. The SPS receiver 406 may comprise any suitablehardware and/or software for receiving and processing SPS signals, suchas global positioning system (GPS) signals. The SPS receiver 406requests information and operations as appropriate from the othersystems, and performs the calculations necessary to determine the UE's400 position using measurements obtained by any suitable SPS algorithm.

One or more sensors 408 may be coupled to a processing system 410 andmay provide means for sensing or detecting information related to thestate and/or environment of the UE 400, such as speed, heading (e.g.,compass heading), headlight status, gas mileage, etc. By way of example,the one or more sensors 408 may include a speedometer, a tachometer, anaccelerometer (e.g., a microelectromechanical systems (MEMS) device), agyroscope, a geomagnetic sensor (e.g., a compass), an altimeter (e.g., abarometric pressure altimeter), etc.

The processing system 410 may include one or more microprocessors,microcontrollers, ASICs, processing cores, digital signal processors, orthe like that provide processing functions, as well as other calculationand control functionality. The processing system 410 may thereforeprovide means for processing, such as means for determining, means forcalculating, means for receiving, means for transmitting, means forindicating, etc. The processing system 410 may include any form of logicsuitable for performing, or causing the components of the UE 400 toperform, at least the techniques described herein.

The processing system 410 may also be coupled to a memory 414 providingmeans for storing (including means for retrieving, means formaintaining, etc.) data and software instructions for executingprogrammed functionality within the UE 400. The memory 414 may beon-board the processing system 410 (e.g., within the same integratedcircuit (IC) package), and/or the memory 414 may be external to theprocessing system 410 and functionally coupled over a data bus.

The UE 400 may include a user interface 416 that provides any suitableinterface systems, such as a microphone/speaker 418, keypad 420, anddisplay 422 that allow user interaction with the UE 400. Themicrophone/speaker 418 may provide for voice communication services withthe UE 400. The keypad 420 may comprise any suitable buttons for userinput to the UE 400. The display 422 may comprise any suitable display,such as, for example, a backlit liquid crystal display (LCD), and mayfurther include a touch screen display for additional user input modes.The user interface 416 may therefore be a means for providingindications (e.g., audible and/or visual indications) to a user and/orfor receiving user input (e.g., via user actuation of a sensing devicesuch a keypad, a touch screen, a microphone, and so on).

In an aspect, the UE 400 may include a sidelink manager 424 coupled tothe processing system 410. The sidelink manager 424 may be a hardware,software, or firmware component that, when executed, causes the UE 400to perform the operations described herein. For example, the sidelinkmanager 424 may be a software module stored in memory 414 and executableby the processing system 410. As another example, the sidelink manager424 may be a hardware circuit (e.g., an ASIC, a field-programmable gatearray (FPGA), etc.) within the UE 400.

FIG. 4B is a block diagram illustrating various components of an exampleroadside assistance unit (RSU) 426, according to aspects of thedisclosure. For the sake of simplicity, the various features andfunctions illustrated in the block diagram of FIG. 4B are connectedtogether using a common data bus that is meant to represent that thesevarious features and functions are operatively coupled together. Thoseskilled in the art will recognize that other connections, mechanisms,features, functions, or the like, may be provided and adapted asnecessary to operatively couple and configure an actual UE. Further, itis also recognized that one or more of the features or functionsillustrated in the example of FIG. 4B may be further subdivided, or twoor more of the features or functions illustrated in FIG. 4B may becombined.

The RSU 426 may include at least one transceiver 404 connected to one ormore antennas 402 and providing means for communicating (e.g., means fortransmitting, means for receiving, means for measuring, means fortuning, means for refraining from transmitting, etc.) with other networknodes, such as VUEs (e.g., VUEs 160), PUEs (e.g., UEs 104), basestations (e.g., base stations 102), etc., via at least one designatedRAT (e.g., cV2X or IEEE 802.11p) over one or more communication links(e.g., communication links 120, sidelinks 162, 166, 168, mmWcommunication link 184). The transceiver 404 may be variously configuredfor transmitting and encoding signals (e.g., messages, indications,information, and so on), and, conversely, for receiving and decodingsignals (e.g., messages, indications, information, pilots, and so on) inaccordance with the designated RAT.

One or more sensors 408 may be coupled to a processing system 410 andmay provide means for sensing or detecting information related to thestate and/or environment of the VRUs in the vicinity of the RSU 426,such as speed, heading (e.g., compass heading), etc. By way of example,the one or more sensors 408 may include a camera or other image sensor,a radio detection and ranging (RADAR), light detection and ranging(LIDAR), ultrasonic, or other type of rangefinder, proximity sensors,pressure sensors, etc.

The processing system 410 may include one or more microprocessors,microcontrollers, ASICs, processing cores, digital signal processors, orthe like that provide processing functions, as well as other calculationand control functionality. The processing system 410 may thereforeprovide means for processing, such as means for determining, means forcalculating, means for receiving, means for transmitting, means forindicating, etc. The processing system 410 may include any form of logicsuitable for performing, or causing the components of the RSU 426 toperform, at least the techniques described herein.

The processing system 410 may also be coupled to a memory 414 providingmeans for storing (including means for retrieving, means formaintaining, etc.) data and software instructions for executingprogrammed functionality within the RSU 426. The memory 414 may beon-board the processing system 410 (e.g., within the same integratedcircuit (IC) package), and/or the memory 414 may be external to theprocessing system 410 and functionally coupled over a data bus.

In an aspect, the RSU 426 may include a sidelink manager 424 coupled tothe processing system 410. The sidelink manager 424 may be a hardware,software, or firmware component that, when executed, causes the RSU 426to perform the operations described herein. For example, the sidelinkmanager 424 may be a software module stored in memory 414 and executableby the processing system 410. As another example, the sidelink manager424 may be a hardware circuit (e.g., an ASIC, a field-programmable gatearray (FPGA), etc.) within the RSU 426.

In an aspect, the RSU 426 may include a network interface 428 forcommunicating with other entities, such as network entities within atelecommunications network, a data network, the Internet, etc. Thenetwork interface 428 may be configured for wired communication,wireless communication, or both.

V2P communication is a powerful tool for ensuring pedestrian safety.Using V2P, a VUE can track the position and velocity of pedestrians withPUEs (VRUs) in the VUE's vicinity and can warn VRUs of potentialcollision with the VUE. A VRU can transmit its position, e.g., obtainedvia GPS, along with its identity to a VUE periodically via public safetymessages (PSMs). However, VRU tracking needs to be very accurate toensure an accurate prediction (and subsequent avoidance, if possible) ofa potential collision between a vehicle and a pedestrian. It istherefore desirable for a vehicle to use other kinds of information, aswell as information from other sources, to track the VRU moreaccurately. One such type of information is ranging information, e.g.,information from which the distance between a VUE and a VRU can bederived.

FIGS. 5 and 6 illustrate a conventional method for pedestrianlocalization. In the scenario illustrated in FIG. 5 , a VUE is in thevicinity of three pedestrians, VRU1, VRU2, and VRU3. In the conventionalmethod 500, the VUE performs ranging operation 502A to VRU1, rangingoperation 502B to VRU2, and ranging operation 502C to VRU3, to determinethe range of each VRU relative to the VUE. Example of ranging operationsinclude, but are not limited to, using a time difference of arrival(TDoA), an angle of arrival (AoA) technique, etc.

FIG. 6 illustrates a conventional method 600 for pedestrianlocalization, using the scenario illustrated in FIG. 5 . In FIG. 6 , theVUE performs a ranging operation to VRUs VRU1 (block 602) through VRU3(block 604). The VUE then repeats this set of ranging operations (block606 and block 608) continually until the VUE is out of range of theVRUs.

FIGS. 7 and 8 illustrate another conventional method for pedestrianlocalization. In the scenario illustrated in FIG. 7 , a VUE is in thevicinity of pedestrians VRU1, VRU2, and VRU3. In the conventional method700, one or more of the VRUs perform a ranging operation, e.g., 702A,702B, 702C, etc., to the VUE and report the results of the rangingoperation to the VUE.

FIG. 8 illustrates a conventional method 800 for pedestrianlocalization, using the scenario illustrated in FIG. 7 . Each of theVRUs performs a ranging operation to the VUE, then sends the rangingdata to the VUE. In FIG. 8 , VRU1 performs a ranging operation to theVUE (block 802), then reports the results of that ranging operation tothe VUE (block 804). The other VRUs do the same, ending with VRU3performing a ranging operation to the VUE (block 806), then reports theresults of that ranging operation to the VUE (block 808). The VRUs mayrepeat these operations periodically or aperiodically upon request to doso by the VUE.

There are technical disadvantages to the conventional methods disclosedabove. For example, in order to determine the location of every VRU inits vicinity, a VUE must receive ranging data from each VRUindividually. In addition, each VUE in the vicinity of a VRU may make asimilar request for ranging information, meaning that a VRU may berequested to perform a ranging operation many times, for many differentVUEs; for battery-powered VRUs, this can be significant drain on itsbattery.

FIG. 9 illustrates a method 900 for pedestrian localization according tosome aspects of the disclosure. FIG. 9 illustrates an aspect in which aVRU may collect range information to a subset of VRUs in its vicinityand provide that information to a VUE along with range information fromthe VRU to the VUE. In the scenario illustrated in FIG. 9 , a VUE is inthe vicinity of pedestrians VRU1, VRU2, and VRU3. According to method900, when a VUE comes into the P2V range of a VRU, that VRU will beginperiodically measuring the distance from that VRU to the VUE and alsomeasuring the distance between that VRU and some of the other VRUsnearby.

In FIG. 9 , for example, when the VUE is in V2P range with VRU1, VRU1periodically performs a ranging operation 902 to the VUE, a rangingoperation 904 to VRU2, and a ranging operation 906 to VRU3, and reportsthe results of those ranging operations to the VUE. VRU1 does notperform a ranging operation to every VRU in its vicinity: for example,in FIG. 9 , VRU1 does not perform a ranging operation to VRU4 or VRU5.

Likewise, in the example illustrated in FIG. 9 , when the VUE is in V2Prange with VRU2, VRU2 periodically performs a ranging operation 908 tothe VUE, a ranging operation 904 to VRU1, a ranging operation 910 toVRU4, and a ranging operation 912 to VRU3, but does not perform aranging operation to VRU5. VRU2 then reports the results of thoseranging operations to the VUE.

Likewise, in the example illustrated in FIG. 9 , when the VUE is in V2Prange with VRU3, VRU3 periodically performs a ranging operation 914 tothe VUE, a ranging operation 906 to VRU1, a ranging operation 912 toVRU2, and a ranging operation 916 to VRU5, but does not perform aranging operation to VRU4. VRU3 then reports the results of thoseranging operations to the VUE.

Each VRU may also provide its own GPS coordinates to the VUE as well.The VUE can then use these measurements and coordinates from the variousVRUs to form a map of pedestrians around the VUE, e.g., using algorithmssuch as multidimensional scaling (with potentially missing entries), ortriangulation methods, to improve on the location estimate of thepedestrian. Algorithms and triangulation methods work when each VRUshares a minimum number of ranging samples (e.g., 3 for triangulation).A VRU may benefit from sharing more ranging samples to help the VUEimprove its location estimate, at the cost of additional batteryconsumption and additional signaling increase the congestion on thewireless medium.

In some aspects, a VUE can perform adaptive sampling, e.g., the VUErequests a VRU to share a specific amount of ranging samples, where thenumber of samples may depend on the VRU's battery level, the VRU levelof danger (e.g., distance and relative velocity to the VUE or to ageographic area 918 associated with a hazard, such as a busyintersection or pedestrian crosswalk, etc.), density of pedestrians(e.g., other VRUs), or other metrics.

For example, a VUE may adapt the ranging request to a VRU to share apreconfigured amount of ranging measurements depending on the VRU'sbattery level. Likewise, the VRU may decide not to request a measurementfrom a specific VRU if that specific VRU has signaled that its batterylevel is less than a specified threshold. In another example, A VUE mayrequest a VRU to perform ranging measurements to a default number ofother VRUs if the requested VRU has a battery level above a firstthreshold, to perform ranging measurements to a number of other VRUssmaller than the default number if the requested VRU has a battery levelbelow the first threshold and above a second threshold, and to performno ranging measurements if the requested VRU has a battery level belowthe second threshold. If a specific VRU has a battery level below thesecond threshold, the VUE may signal other VRUs to performing rangingmeasurements to the specific VRU so that the specific VRU does not haveto perform those operations and thus reduce the battery consumption ofthat specific VRU. In other words, the VUE leverages the symmetryproperty of ranging by requesting neighboring VRUs to provide rangingdata about the VRU of interest.

In some aspects, the VUE requests each VRU to share ranging data with apreconfigured number/set of other VRUs in its vicinity, where the amountof requested ranging data by VUE depends on the density of other VRUs inthe vicinity of the particular VRU to which the request is being sent.In some aspects, VRU density in the vicinity of a VRU defined as thenumber of distinct VRUs (as defined by VRU identifier) that a particularVRU can detect in an area (e.g., defined with the particular VRU'slocation as center and a preconfigured radius R meters). For example, ifthe VRU density is greater than a threshold density, VRU1 needs toreport x unique ranging measurements, or y % of the sensed VRU density.

In some aspects, a VUE may additionally request a VRU to perform rangingwith specific VRUs by providing a list of VRU identifiers, which may be,for example, VRUs that have a very accurate location estimate, allowingthe VUE to propagate the strong location confidence to other VRUs.

In some aspects, each VRU may be preconfigured to periodically performthe ranging operation, or periodically perform the ranging operation inresponse to detection of a trigger condition. Examples of triggerconditions include, but are not limited to, receipt of a public servicemessage (PSM) from a VUE or an RSU or detection that the VRU is in ornear a specified geographic position or area (e.g., near a busy ordangerous intersection). In the latter case, the geographic position orarea may be specified by a VUE or RSU, may be preconfigured to the VRU,or combinations thereof.

In some aspects, each VRU may perform the ranging operation uponreception of an explicit request to perform such an operation. Thisexplicit request can be sent by a VUE, an RSU, or another VRU. Theexplicit request may include a list of VRUs for which ranging data isdesired, e.g., the list of VRUs is decided by requesting entity, or theexplicit request may specify a number of VRUs to be measured and the VRUreceiving that request decides which VRUs to range. In some aspects, thelist of VRUs may be selected randomly or by some selection algorithm,including, but not limited to, the selection algorithms described above.In some aspects, the selecting entity (VUE, VRU, or RSU) can select oravoid selecting specific VRUs based on selection criteria. Examples ofselection criteria include, but are not limited to, selection of a VRUbased on: a battery level of the VRU; a battery level of another VRU(e.g., leveraging the symmetry property as described above); atrajectory or anticipated trajectory of the VRU; a proximity oranticipated proximity of the VRU to a danger or hazard; a proximity oranticipated proximity of the VRU to another VRU; a level of confidenceof a geographic location of the VRU; a capability of the VRU; a mobilitystatus of the VRU; a number or relative density of PUEs in, oranticipated to be in, the vicinity of the VRU; or combinations thereof.

FIG. 10 illustrates a method 1000 for pedestrian localization accordingto some aspects of the disclosure. FIG. 10 illustrates an aspect inwhich a VRU may collect range information to a subset of VRUs in itsvicinity and provide that information to a VUE along with rangeinformation from the VRU to the VUE. FIG. 10 shows example operationstaken by the VUE and VRUs in FIG. 9 , but the same concepts may beapplied to other scenarios involving one or more VUEs and one or moreVRUs. In the example shown in FIG. 10 , VRU1 performs a rangingoperation 1002 to the VUE, a ranging operation 1004 to VRU2, and aranging operation 1006 to VRU3, then reports the ranging data, includingits GPS location, to the VUE (signal 1008). The order of rangingoperations shown in FIG. 10 are illustrative and not limiting. In theexample shown in FIG. 10 , VRU2 performs a ranging operation 1010 to theVUE, a ranging operation 1012 to VRU1, and a ranging operation 1014 toVRU3, then reports the ranging data, including its GPS location, to theVUE (signal 1016). In the example shown in FIG. 10 , VRU3 performs aranging operation 1018 to the VUE, a ranging operation 1020 to VRU1, anda ranging operation 1022 to VRU3, then reports the ranging data,including its GPS location, to the VUE (signal 1024). The VUE then usesthe received ranging data to update the estimated positions of VRU1,VRU2, and VRU3 (block 1026). In the example illustrated in FIG. 10 , theVUE updates the estimated positions after all data has been received,but alternatively, the VUE may update the estimated position of one ormore of the VRUs every time it receives ranging data from any VRU, oraccording to some other algorithm. In some aspects, a VRU may performthe ranging operations in response to receiving a PSM from a VUE.

In some aspects, the VRU may choose whether or not to perform theranging operations based on whether or not the VRU is currently moving.For example, a PUE possessed by a person not currently moving, e.g.,someone eating at an outdoor cafe, may choose not to engage in rangingoperations, e.g., because the likelihood that that person will be movinginto the path of an oncoming vehicle is low. Likewise, a VRU, whethermoving or not, that receives a PSM from a VUE that is currently notmoving (e.g., a parked car), may decide not to perform rangingoperations for that VUE. In some aspects, a VUE may notify VRUs of itsapproach, and instruct the VRUs to configure themselves so that, whenand if the VRU approaches the curb, that VRU should transmit itsposition to the VUE more frequently.

FIG. 11 illustrates a method 1100 for pedestrian localization accordingto some aspects of the disclosure. FIG. 11 illustrates an aspect inwhich a VRU may collect range information to a subset of VRUs in itsvicinity and provide that information to a VUE along with rangeinformation from the VRU to the VUE. FIG. 11 shows example operationstaken by the VUE and VRUs in FIG. 9 , but the same concepts may beapplied to other scenarios involving one or more VUEs and one or moreVRUs. In the example shown in FIG. 11 , the VUE sends, to VRU1, arequest 1102 for ranging data from a specified set of VRUs, e.g., VRU2and VRU3. VRU1 performs a ranging operation 1104 to the VUE, a rangingoperation 1106 to VRU2, and a ranging operation 1108 to VRU3, thenreports the ranging data, including its GPS location, to the VUE (signal1110). The order of ranging operations shown in FIG. 11 are illustrativeand not limiting. In the example shown in FIG. 11 , VRU1 also sends tothe VUE an indication of VRU1 battery level, which in this scenario islow. The VUE then updates its location estimates for VRU1, VRU2, andVRU3 (block 1112). Because VRU1's battery level is low, VUE demotesVRU1, i.e., removes VRU1 from consideration for receiving a request forranging data. In the example illustrated in FIG. 11 , the VUE thensends, to VRU2, a request 1114 for ranging data from a specified set ofVRUs, e.g., VRU1 and VRU3. VRU2 performs a ranging operation 1116 to theVUE, a ranging operation 1118 to VRU1, and a ranging operation 1120 toVRU3, then reports the ranging data, including its GPS location, to theVUE (signal 1122). The VUE then uses the received ranging data to updatethe estimated positions of VRU1, VRU2, and VRU3 (block 1124).

FIG. 12 illustrates a method 1200 for pedestrian localization accordingto some aspects of the disclosure. In the scenario illustrated in FIG.12 , pedestrians VRU1, VRU2, and VRU3 are in the vicinity of an RSU, asare VUE1 and VUE2. FIG. 12 illustrates an aspect in which a VRU maycollect range information to a subset of VRUs in its vicinity andprovide that information to an RSU along with range information from theVRU to the RSU. In this manner an RSU may collect range information to asubset of VRUs in its vicinity and provide that information to one ormore VUEs. In some aspects, the RSU manages the selection of VRUs in itsvicinity and interacts with VUEs as needed. This approach has theadvantage that the RSU operates as a mediator or buffer between VUEs andVRUs, with the result that the each VRU may take instructions from oneentity—the RSU—rather than from many entities—the one or more VUEs. Insome aspects, an RSU may also use additional data, such as sensor data(e.g., images from a camera mounted to the RSU, for example) to identifyVRUs that should participate in the ranging operations. In some aspects,an RSU may use sensor data to detect moving, non-PUE obstacles, such asanimals, and notify a VUE or VRU of the presence and position of thoseobstacles. In some aspects, an RSU may be configured to detect radiocollars, near-field communication (NFC) tags, or other devices that maybe attached to a pet collar, leash, etc., and thereby detect pets andprovide their locations to VUEs for assistance in collision avoidance.

In some aspects, an RSU may instruct a VRU to perform a range operationto one or more VUEs, but the VRU is not flooded with requests from everyVUE in its vicinity. Instead, each VUE may coordinate with the RSU toget position estimates for VRUs in the vicinity of the particular VUE.Furthermore, because the RSU's location is static (unlike the VUEs), theRSU can take into account features of the environment in its vicinity,such as barriers, obstacles, and hazards, etc., when selecting VRUs forparticipation in ranging operations. For example, an RSU may detect thata VRU, e.g., VRU3 in FIG. 12 , is in or is approaching a hazardous zone1202, and in response instruct VRU3 to provide ranging information morefrequently than other VRUs not in or near the hazardous zone 1202. Insome aspects, the RSU or VUE may instruct a first VRU to perform andreport ranging information for a second VRU that the first VRUdetermines is within, near, or heading toward the hazardous zone 1202 orin another zone specified by the RSU or VUE.

In some aspects, when a VRU comes in the RSU's PSM range, the VRUperiodically measures the distance separating it to the RSU and to someVRUs around it, using e.g., TDoA technique, and sends the ranging datato the RSU. These measurements can be used by the RSU to form a map ofpedestrians around it using algorithms such as Multidimensional Scaling(with potentially missing entries), or triangulation methods to improveon the location estimate of the pedestrian. The VRU needs to share itsGPS coordinate as well, to be used as an anchor.

In FIG. 12 , for example, when VRU1 is in pedestrian to infrastructure(P2I) range with the RSU, VRU1 may periodically perform a rangingoperation 1204 to VRU2, and a ranging operation 1206 to VRU3, and reportthe results of those ranging operations to the RSU (signal 1208). VRU1may also perform a ranging operation to the RSU and include that rangedata with the results. In some aspects, VRU1 may also perform a rangingoperation to a VUE if instructed to do so by the RSU. In FIG. 12 , forexample, VRU1 may perform a ranging operation 1210 to VUE1 and a rangingoperation 1212 to VUE2, but does not perform a ranging operation to VRU4or VRU5.

Likewise, in the example illustrated in FIG. 12 , when VRU2 is in P2Irange with the RSU, VRU2 may periodically perform a ranging operation1204 to VRU1, and a ranging operation 1214 to VRU3, and a rangingoperation 1216 to VRU4, and report the results of those rangingoperations to the RSU (signal 1218). VRU2 may also perform a rangingoperation to the RSU and include that range data with the results.

Likewise, in the example illustrated in FIG. 12 , when VRU3 is in P2Irange with the RSU, VRU3 may periodically perform a ranging operation1206 to VRU1, and a ranging operation 1214 to VRU2, and a rangingoperation 1220 to VRU5, and report the results of those rangingoperations to the RSU (signal 1222). VRU3 may also perform a rangingoperation to the RSU and include that range data with the results. Insome aspects, VRU3 may also perform a ranging operation to a VUE ifinstructed to do so by the RSU. In FIG. 12 , for example, VRU3 mayperform a ranging operation 1224 to VUE2.

Each VRU may also provide its own GPS coordinates to the RSU as well.The RSU can then use these measurements and coordinates from the variousVRUs to form a map of pedestrians around the RSU, e.g., using algorithmssuch as multidimensional scaling (with potentially missing entries), ortriangulation methods, to improve on the location estimate of thepedestrian. Algorithms and triangulation methods work when each VRUshares a minimum number of ranging samples (e.g., 3 for triangulation).A VRU may benefit from sharing more ranging samples to help the RSUimprove its location estimate, at the cost of additional batteryconsumption and additional signaling increase the congestion on thewireless medium.

In some aspects, an RSU can perform adaptive sampling, e.g., the RSUrequests a VRU to share a specific amount of ranging samples, where thenumber of samples may depend on the VRU's battery level, the VRU levelof danger (e.g., distance and relative velocity to the RSU), density ofpedestrians (e.g., other VRUs), or other metrics.

For example, an RSU may adapt the ranging request to a VRU to share apreconfigured amount of ranging measurements depending on the VRU'sbattery level. Likewise, the VRU may decide not to request a measurementfrom a specific VRU if that specific VRU has signaled that its batterylevel is less than a specified threshold. In another example, A RSU mayrequest a VRU to perform ranging measurements to a default number ofother VRUs if the requested VRU has a battery level above a firstthreshold, to perform ranging measurements to a number of other VRUssmaller than the default number if the requested VRU has a battery levelbelow the first threshold and above a second threshold, and to performno ranging measurements if the requested VRU has a battery level belowthe second threshold. If a specific VRU has a battery level below thesecond threshold, the RSU may signal other VRUs to performing rangingmeasurements to the specific VRU so that the specific VRU does not haveto perform those operations and thus reduce the battery consumption ofthat specific VRU. In other words, the RSU leverages the symmetryproperty of ranging by requesting neighboring VRUs to provide rangingdata about the VRU of interest.

In some aspects, the RSU requests each VRU to share ranging data with apreconfigured number/set of other VRUs in its vicinity, where the amountof requested ranging data by RSU depends on the density of other VRUs inthe vicinity of the particular VRU to which the request is being sent.In some aspects, VRU density in the vicinity of a VRU defined as thenumber of distinct VRUs (as defined by VRU identifier) that a particularVRU can detect in an area (e.g., defined with the particular VRU'slocation as center and a preconfigured radius R meters). For example, ifthe VRU density is greater than a threshold density, VRU1 needs toreport x unique ranging measurements, or y % of the sensed VRU density.

In some aspects, an RSU may additionally request a VRU to performranging with specific VRUs by providing a list of VRU identifiers, whichmay be, for example, VRUs that have a very accurate location estimate,allowing the RSU to propagate the strong location confidence to otherVRUs.

In some aspects, each VRU may be preconfigured to periodically performthe ranging operation, or periodically perform the ranging operation inresponse to detection of a trigger condition. Examples of triggerconditions include, but are not limited to, receipt of a public servicemessage (PSM) from an RSU or an RSU or detection that the VRU is in ornear a specified geographic position or area (e.g., near a busy ordangerous intersection). In the latter case, the geographic position orarea may be specified by a VUE or RSU, may be preconfigured to the VRU,or combinations thereof.

In some aspects, each VRU may perform the ranging operation uponreception of an explicit request to perform such an operation. Thisexplicit request can be sent by an RSU, a VUE, or another VRU. Theexplicit request may include a list of VRUs for which ranging data isdesired, e.g., the list of VRUs is decided by requesting entity, or theexplicit request may specify a number of VRUs to be measured and the VRUreceiving that request decides which VRUs to range. In some aspects, thelist of VRUs may be selected randomly or by some selection algorithm,including, but not limited to, the selection algorithms described above.In some aspects, the selecting entity (VUE, VRU, or RSU) can select oravoid selecting specific VRUs based on selection criteria. Examples ofselection criteria include, but are not limited to, selection of a VRUbased on: a battery level of the VRU; a battery level of another VRU(e.g., leveraging the symmetry property as described above); atrajectory or anticipated trajectory of the VRU; a proximity oranticipated proximity of the VRU to a danger or hazard; a proximity oranticipated proximity of the VRU to another VRU; a level of confidenceof a geographic location of the VRU; a capability of the VRU; a mobilitystatus of the VRU; a number or relative density of PUEs in, oranticipated to be in, the vicinity of the VRU; or combinations thereof.

FIG. 13 illustrates a method 1300 for pedestrian localization accordingto some aspects of the disclosure. FIG. 13 illustrates an aspect inwhich a VRU may collect range information to a subset of VRUs in itsvicinity and provide that information to an RSU, which can then updateVRU location estimates and optionally provide those estimates to VUEs.FIG. 13 shows example operations taken by RSU, VRUs, and VUEs shown inthe example illustrated in FIG. 12 , but the same concepts may beapplied to other scenarios involving different numbers of RSUs, VRUs,and VUEs. In the example shown in FIG. 13 , the RSU sends, to VRU1, arequest 1302 for ranging data. In response, VRU1 performs a set ofranging operations 1304, and sends ranging data 1306 to the RSU. In someaspects, the ranging data includes GPS or other location information forVRU1 as well as VRU1's battery level. The RSU updates VRU locationestimates (block 1308) and sends the updated VRU locations to VUE1(signal 1310) and VUE2 (signal 1312). In the example shown in FIG. 13 ,the RSU sends, to VRU2, a request 1314 for ranging data. In response,VRU2 performs a set of ranging operations 1316, and sends ranging data1318 to the RSU. In some aspects, the ranging data includes GPS or otherlocation information for VRU2 as well as VRU2's battery level. The RSUupdates VRU location estimates (block 1320) and sends the updated VRUlocations to VUE1 (signal 1322) and VUE2 (signal 1324). In the exampleshown in FIG. 13 , the RSU sends, to VRU3, a request 1326 for rangingdata. In response, VRU3 performs a set of ranging operations 1328, andsends ranging data 1330 to the RSU. In some aspects, the ranging dataincludes GPS or other location information for VRU3 as well as VRU3'sbattery level. The RSU updates VRU location estimates (block 1332) andsends the updated VRU locations to VUE1 (signal 1334) and VUE2 (signal1336).

FIG. 14 is a flowchart of an example process 1400 associated withranging assisted pedestrian localization. In some aspects, one or moreprocess blocks of FIG. 14 may be performed by a pedestrian userequipment (PUE) (e.g., UE 400). In some aspects, one or more processblocks of FIG. 14 may be performed by another device or a group ofdevices separate from or including the pedestrian user equipment (PUE).Additionally, or alternatively, one or more process blocks of FIG. 14may be performed by one or more components of device 400, such asprocessing system 410, memory 414, transceiver 404, sensors 408,sidelink manager 424, user interface 416, etc.

As shown in FIG. 14 , process 1400 may include performing a rangingoperation to a set of user equipment (UEs), the set comprising at leasta second PUE (block 1410). For example, the PUE may perform a rangingoperation to a set of user equipment (UEs), the set comprising at leasta second PUE, as described above.

As further shown in FIG. 14 , process 1400 may include providing rangingdata to a third entity, the third entity comprising a vehicle userequipment (VUE) or a road-side unit (RSU) (block 1420). For example, thePUE may provide ranging data to a third entity, the third entitycomprising a vehicle user equipment (VUE) or a road-side unit (RSU), asdescribed above. In some aspects, the ranging data comprises locationinformation, the location information identifying a location of thefirst PUE, a location of at least one of the set of UEs, or combinationsthereof. In some aspects, the location information comprises globalpositioning system (GPS) information. In some aspects, the third entityis a member of the set of UEs.

In some aspects, the ranging operation to the set of UEs is performedperiodically. In some aspects, the ranging operation to the set of UEsis performed in response to detecting a trigger condition. In someaspects, detecting the trigger condition comprises detecting that thefirst PUE is within, or within a threshold distance from, apredetermined geographic area. In some aspects, the predeterminedgeographic area is specified by the third entity. In some aspects,detecting the trigger condition comprises receiving a request to performthe ranging operation. In some aspects, the request to perform theranging operation is received from the third entity, from the secondPUE, or from a third PUE.

In some aspects, the set of UEs is selected by the first PUE. In someaspects, the set of UEs is selected by the third entity and wherein therequest to perform the ranging operation comprises informationidentifying the set of other UEs. In some aspects, at least one memberof the set of UEs is selected based on a battery level of the onemember, a battery level of another member of the set of UEs, atrajectory or anticipated trajectory of the one member, a proximity oranticipated proximity of the one member to a danger or hazard, aproximity or anticipated proximity of the one member to another memberof the set of UEs, a level of confidence of a geographic location of theone member, a capability of the one member, a mobility status of the onemember, a number or relative density of PUEs in, or anticipated to bein, the vicinity of the one member, or combinations thereof.

Although FIG. 14 shows example blocks of process 1400, in some aspects,process 1400 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 14 .Additionally, or alternatively, two or more of the blocks of process1400 may be performed in parallel.

FIG. 15 is a flowchart of an example process 1500 associated withranging assisted pedestrian localization. In some aspects, one or moreprocess blocks of FIG. 15 may be performed by a vehicle user equipment(VUE) (e.g., UE 400). In some aspects, one or more process blocks ofFIG. 15 may be performed by another device or a group of devicesseparate from or including the vehicle user equipment (VUE).Additionally, or alternatively, one or more process blocks of FIG. 15may be performed by one or more components of device 400, such asprocessing system 410, memory 414, transceiver 404, sensors 408,sidelink manager 424, user interface 416, etc.

As shown in FIG. 15 , process 1500 may include sending, to a firstpedestrian user equipment (PUE), a request to perform a rangingoperation to a set of user equipment (UEs), the set comprising at leasta second PUE (block 1510). For example, the VUE may send, to a firstpedestrian user equipment (PUE), a request to perform a rangingoperation to a set of user equipment (UEs), the set comprising at leasta second PUE, as described above.

As further shown in FIG. 15 , process 1500 may include receiving, fromthe first PUE, ranging data indicating a range from the first PUE toeach member of the set of UEs (block 1520). For example, the VUE mayreceive, from the first PUE, ranging data indicating a range from thefirst PUE to each member of the set of UEs, as described above.

As further shown in FIG. 15 , process 1500 may include determining,based on the ranging data, an estimated position for each UE in the setof UEs (block 1530). For example, the VUE may determine, based on theranging data, an estimated position for each UE in the set of UEs, asdescribed above. In some aspects, the ranging data comprises locationinformation, the location information identifying a location of thefirst PUE, a location of at least one of the set of UEs, or combinationsthereof. In some aspects, the location information comprises globalpositioning system (GPS) information. In some aspects, the ranging datafurther indicates a range from the first PUE to the VUE.

In some aspects, requesting indicates that the ranging operation to theset of UEs is to be performed periodically. In some aspects, the requestidentifies a trigger condition upon detection of which the rangingoperation is to be performed. In some aspects, the trigger conditioncomprises detecting that the first PUE is within, or within a thresholddistance from, a predetermined geographic area. In some aspects, thepredetermined geographic area is specified by the VUE or by a thirdentity.

In some aspects, the set of UEs is selected by the first PUE. In someaspects, the set of UEs is selected by the VUE and wherein the requestto perform the ranging operation comprises information identifying theset of UEs. In some aspects, at least one member of the set of UEs isselected based on a battery level of the one member, a battery level ofanother member of the set of UEs, a trajectory or anticipated trajectoryof the one member, a proximity or anticipated proximity of the onemember to a danger or hazard, a proximity or anticipated proximity ofthe one member to another member of the set of UEs, a level ofconfidence of a geographic location of the one member, a capability ofthe one member, a mobility status of the one member, a number orrelative density of PUEs in, or anticipated to be in, the vicinity ofthe one member, or combinations thereof.

Although FIG. 15 shows example blocks of process 1500, in some aspects,process 1500 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 15 .Additionally, or alternatively, two or more of the blocks of process1500 may be performed in parallel.

FIG. 16 is a flowchart of an example process 1600 associated withranging assisted pedestrian localization. In some aspects, one or moreprocess blocks of FIG. 16 may be performed by a road-side unit (RSU)(e.g., RSU 426). In some aspects, one or more process blocks of FIG. 16may be performed by another device or a group of devices separate fromor including the road-side unit (RSU). Additionally, or alternatively,one or more process blocks of FIG. 16 may be performed by one or morecomponents of RSU 426, such as processing system 410, memory 414,transceiver 404, sensors 408, sidelink manager 424, etc.

As shown in FIG. 16 , process 1600 may include sending, to a firstpedestrian user equipment (PUE), a request to perform a rangingoperation to a set of user equipment (UEs), the set comprising at leasta second PUE (block 1610). For example, the road-side unit (RSU) maysend, to a first pedestrian user equipment (PUE), a request to perform aranging operation to a set of user equipment (UEs), the set comprisingat least a second PUE, as described above. In some aspects, the requestindicates that the ranging operation to the set of UEs is to beperformed periodically. In some aspects, the request identifies atrigger condition upon detection of which the ranging operation is to beperformed. In some aspects, the trigger condition comprises detectingthat the first PUE is within, or within a threshold distance from, apredetermined geographic area. In some aspects, the predeterminedgeographic area is specified by the RSU, by the VUE, or by a thirdentity.

In some aspects, the set of UEs is selected by the first PUE. In someaspects, the set of UEs is selected by the RSU or by the VUE and whereinthe request to perform the ranging operation comprises informationidentifying the set of UEs. In some aspects, at least one member of theset of UEs is selected based on a battery level of the one member, abattery level of another member of the set of UEs a trajectory oranticipated trajectory of the one member, a proximity or anticipatedproximity of the one member to a danger or hazard, a proximity oranticipated proximity of the one member to another member of the set ofUEs, a level of confidence of a geographic location of the one member, acapability of the one member, a mobility status of the one member, anumber or relative density of PUEs in, or anticipated to be in, thevicinity of the one member, or combinations thereof.

As further shown in FIG. 16 , process 1600 may include receiving, fromthe first PUE, ranging data indicating a range from the first PUE toeach member of the set of UEs (block 1620). For example, the road-sideunit (RSU) may receive, from the first PUE, ranging data indicating arange from the first PUE to each member of the set of UEs, as describedabove. In some aspects, the ranging data comprises location information,the location information identifying a location of the first PUE, alocation of at least one of the set of UEs, or combinations thereof. Insome aspects, the location information comprises global positioningsystem (GPS) information. In some aspects, the ranging informationfurther indicates a range from the first PUE to the RSU.

As further shown in FIG. 16 , process 1600 may include sending, to avehicle UE (VUE), the ranging data, an estimated position of each memberof the set of UEs, or combinations thereof (block 1630). For example,the road-side unit (RSU) may send, to a vehicle UE (VUE), the rangingdata, an estimated position of each member of the set of UEs, orcombinations thereof, as described above.

Although FIG. 16 shows example blocks of process 1600, in some aspects,process 1600 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 16 .Additionally, or alternatively, two or more of the blocks of process1600 may be performed in parallel.

FIG. 17 is a flowchart of an example process 1700 associated withranging assisted pedestrian localization. In some aspects, one or moreprocess blocks of FIG. 17 may be performed by a vulnerable road user(e.g., any of the VRUs or PUEs described herein). In some aspects, oneor more process blocks of FIG. 17 may be performed by one or morecomponents of device 400, such as processing system 410, memory 414,transceiver 404, sensors 408, sidelink manager 424, user interface 416,etc.

As shown in FIG. 17 , process 1700 may include, at block 1710,determining whether a VRU has received an inter-VRU reportingconfiguration from another node, e.g., from an RSU or VUE. If not, thenthe process 1700 moves to block 1720, and if so, then the process 1700moves to block 1730. At block 1720, the process 1700 includes performingranging measurements based on a pre-configuration, and at block 1730,the process 1700 includes performing measurements based on an updatedconfiguration. A pre-configuration or updated configuration may considera number of factors to determine how many and which ranging measurementsshould be performed. Examples of factors include, but are not limitedto, the battery level of the device, the number of other VRUs sensed inthe vicinity of the device, and the geography in the vicinity of thedevice.

As shown in FIG. 17 , process 1700 may further include, at block 1740,reporting the inter-VRU ranging measurements taken based on thepre-configuration or the updated configuration.

Although FIG. 17 shows example blocks of process 1700, in some aspects,process 1700 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 17 .

Some of all of the techniques described herein may be used todynamically modify the communication between VUEs, VRUs, and RSUs inresponse to changing conditions to concentrate communication on VRUsthat are in danger or likely to have a potential collision.

In the detailed description above it can be seen that different featuresare grouped together in examples. This manner of disclosure should notbe understood as an intention that the example clauses have morefeatures than are explicitly mentioned in each clause. Rather, thevarious aspects of the disclosure may include fewer than all features ofan individual example clause disclosed. Therefore, the following clausesshould hereby be deemed to be incorporated in the description, whereineach clause by itself can stand as a separate example. Although eachdependent clause can refer in the clauses to a specific combination withone of the other clauses, the aspect(s) of that dependent clause are notlimited to the specific combination. It will be appreciated that otherexample clauses can also include a combination of the dependent clauseaspect(s) with the subject matter of any other dependent clause orindependent clause or a combination of any feature with other dependentand independent clauses. The various aspects disclosed herein expresslyinclude these combinations, unless it is explicitly expressed or can bereadily inferred that a specific combination is not intended (e.g.,contradictory aspects, such as defining an element as both an insulatorand a conductor). Furthermore, it is also intended that aspects of aclause can be included in any other independent clause, even if theclause is not directly dependent on the independent clause.

Aspect examples are described in the following numbered clauses:

Clause 1. A method of wireless communication performed by a firstpedestrian user equipment (PUE), the method comprising: performing aranging operation to a set of user equipment (UEs), the set comprisingat least a second PUE; and providing ranging data to a third entity, thethird entity comprising a vehicle user equipment (VUE) or a road-sideunit (RSU).

Clause 2. The method of clause 1, where the ranging data compriseslocation information, the location information identifying a location ofthe first PUE, a location of at least one of the set of UEs, orcombinations thereof.

Clause 3. The method of clause 2, wherein the location informationcomprises global positioning system (GPS) information.

Clause 4. The method of any of clauses 1 to 3, wherein the third entityis a member of the set of UEs.

Clause 5. The method of any of clauses 1 to 4, wherein the rangingoperation to the set of UEs is performed periodically.

Clause 6. The method of any of clauses 1 to 5, wherein the rangingoperation to the set of UEs is performed in response to detecting atrigger condition.

Clause 7. The method of clause 6, wherein detecting the triggercondition comprises detecting that the first PUE is within, or within athreshold distance from, a predetermined geographic area.

Clause 8. The method of clause 7, wherein the predetermined geographicarea is specified by the third entity.

Clause 9. The method of any of clauses 6 to 8, wherein detecting thetrigger condition comprises receiving a request to perform the rangingoperation.

Clause 10. The method of clause 9, wherein the request to perform theranging operation is received from the third entity, from the secondPUE, or from a third PUE.

Clause 11. The method of any of clauses 9 to 10, wherein the set of UEsis selected by the third entity and wherein the request to perform theranging operation comprises information identifying the set of UEs.

Clause 12. The method of any of clauses 1 to 11, wherein the set of UEsis selected by the first PUE.

Clause 13. The method of any of clauses 1 to 12, wherein at least onemember of the set of UEs is selected based on: a battery level of the atleast one member; a battery level of another member of the set of UEs; atrajectory or anticipated trajectory of the one member; a proximity oranticipated proximity of the one member to a danger or hazard; aproximity or anticipated proximity of the one member to another memberof the set of UEs; a level of confidence of a geographic location of theone member; a capability of the one member; a mobility status of the onemember; or combinations thereof.

Clause 14. The method of any of clauses 1 to 13, wherein the number ofUEs in the set of UEs is based on a number or relative density of PUEsin, or anticipated to be in, a vicinity of the first PUE.

Clause 15. The method of clause 14, wherein the vicinity of the firstPUE comprises an area having the first PUE as center and a preconfiguredradius.

Clause 16. The method of any of clauses 14 to 15, wherein the number ofUEs in the set of UEs is calculated as a preconfigured number of PUEs inthe vicinity of the first PUE or a preconfigured percentage of thedensity of PUEs in the vicinity of the first PUE.

Clause 17. The method of clause 16, wherein the preconfigured number orthe preconfigured percentage is selected based on one or more densitythresholds of the density of PUEs in the vicinity of the first PUE.

Clause 18. A method of wireless communication performed by a vehicleuser equipment (VUE), the method comprising: sending, to a firstpedestrian user equipment (PUE), a request to perform a rangingoperation to a set of user equipment (UEs), the set comprising at leasta second PUE; receiving, from the first PUE, ranging data indicating arange from the first PUE to each member of the set of UEs; anddetermining, based on the ranging data, an estimated position for eachUE in the set of UEs.

Clause 19. The method of clause 18, where the ranging data compriseslocation information, the location information identifying a location ofthe first PUE, a location of at least one of the set of UEs, orcombinations thereof.

Clause 20. The method of clause 19, wherein the location informationcomprises global positioning system (GPS) information.

Clause 21. The method of any of clauses 18 to 20, wherein the rangingdata further indicates a range from the first PUE to the VUE.

Clause 22. The method of any of clauses 18 to 21, wherein the requestindicates that the ranging operation to the set of UEs is to beperformed periodically.

Clause 23. The method of any of clauses 18 to 22, wherein the requestidentifies a trigger condition upon detection of which the rangingoperation is to be performed.

Clause 24. The method of clause 23, wherein the trigger conditioncomprises detecting that the first PUE is within, or within a thresholddistance from, a predetermined geographic area.

Clause 25. The method of clause 24, wherein the predetermined geographicarea is specified by the VUE or by a third entity.

Clause 26. The method of any of clauses 18 to 25, wherein the set of UEsis selected by the VUE and wherein the request to perform the rangingoperation comprises information identifying the set of UEs.

Clause 27. The method of any of clauses 18 to 26, wherein the set of UEsis selected by the first PUE.

Clause 28. The method of any of clauses 18 to 27, wherein at least onemember of the set of UEs is selected based on: a battery level of the atleast one member; a battery level of another member of the set of UEs; atrajectory or anticipated trajectory of the one member; a proximity oranticipated proximity of the one member to a danger or hazard; aproximity or anticipated proximity of the one member to another memberof the set of UEs; a level of confidence of a geographic location of theone member; a capability of the one member; a mobility status of the onemember; or combinations thereof.

Clause 29. The method of any of clauses 18 to 28, wherein the number ofUEs in the set of UEs is based on a number or relative density of PUEsin, or anticipated to be in, a vicinity of the first PUE.

Clause 30. The method of clause 29, wherein the vicinity of the firstPUE comprises an area having the first PUE as center and a preconfiguredradius.

Clause 31. The method of any of clauses 29 to 30, wherein the number ofUEs in the set of UEs is calculated as a preconfigured number of PUEs inthe vicinity of the first PUE or a preconfigured percentage of thedensity of PUEs in the vicinity of the first PUE.

Clause 32. The method of clause 31, wherein the preconfigured number orthe preconfigured percentage is selected based on one or more densitythresholds of the density of PUEs in the vicinity of the first PUE.

Clause 33. A method of wireless communication performed by a road-sideunit (RSU), the method comprising: sending, to a first pedestrian userequipment (PUE), a request to perform a ranging operation to a set ofuser equipment (UEs), the set comprising at least a second PUE;receiving, from the first PUE, ranging data indicating a range from thefirst PUE to each member of the set of UEs; and sending, to a vehicle UE(VUE), the ranging data, an estimated position of each member of the setof UEs, or combinations thereof.

Clause 34. The method of clause 33, where the ranging data compriseslocation information, the location information identifying a location ofthe first PUE, a location of at least one of the set of UEs, orcombinations thereof.

Clause 35. The method of clause 34, wherein the location informationcomprises global positioning system (GPS) information.

Clause 36. The method of any of clauses 33 to 35, wherein the rangingdata further indicates a range from the first PUE to the RSU.

Clause 37. The method of any of clauses 33 to 36, wherein the requestindicates that the ranging operation to the set of UEs is to beperformed periodically.

Clause 38. The method of any of clauses 33 to 37, wherein the requestidentifies a trigger condition upon detection of which the rangingoperation is to be performed.

Clause 39. The method of clause 38, wherein the trigger conditioncomprises detecting that the first PUE is within, or within a thresholddistance from, a predetermined geographic area.

Clause 40. The method of clause 39, wherein the predetermined geographicarea is specified by the RSU, by the VUE, or by a third entity.

Clause 41. The method of any of clauses 33 to 40, wherein the set of UEsis selected by the first PUE.

Clause 42. The method of any of clauses 33 to 41, wherein the set of UEsis selected by the RSU or by the VUE and wherein the request to performthe ranging operation comprises information identifying the set of UEs.

Clause 43. The method of any of clauses 33 to 42, wherein at least onemember of the set of UEs is selected based on: a battery level of the atleast one member; a battery level of another member of the set of UEs atrajectory or anticipated trajectory of the one member; a proximity oranticipated proximity of the one member to a danger or hazard; aproximity or anticipated proximity of the one member to another memberof the set of UEs; a level of confidence of a geographic location of theone member; a capability of the one member; a mobility status of the onemember; a number or relative density of PUEs in, or anticipated to bein, a vicinity of the one member; or combinations thereof.

Clause 44. The method of any of clauses 33 to 43, wherein the number ofUEs in the set of UEs is based on a number or relative density of PUEsin, or anticipated to be in, a vicinity of the first PUE.

Clause 45. The method of clause 44, wherein the vicinity of the firstPUE comprises an area having the first PUE as center and a preconfiguredradius.

Clause 46. The method of any of clauses 44 to 45, wherein the number ofUEs in the set of UEs is calculated as a preconfigured number of PUEs inthe vicinity of the first PUE or a preconfigured percentage of thedensity of PUEs in the vicinity of the first PUE.

Clause 47. The method of clause 46, wherein the preconfigured number orthe preconfigured percentage is selected based on one or more densitythresholds of the density of PUEs in the vicinity of the first PUE.

Clause 48. An apparatus comprising a memory and at least one processorcommunicatively coupled to the memory, the memory and the at least oneprocessor configured to perform a method according to any of clauses 1to 47.

Clause 49. An apparatus comprising means for performing a methodaccording to any of clauses 1 to 47.

Clause 50. A non-transitory computer-readable medium storingcomputer-executable instructions, the computer-executable comprising atleast one instruction for causing a computer or processor to perform amethod according to any of clauses 1 to 47.

Those of skill in the art will appreciate that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Further, those of skill in the art will appreciate that the variousillustrative logical blocks, modules, circuits, and algorithm stepsdescribed in connection with the aspects disclosed herein may beimplemented as electronic hardware, computer software, or combinationsof both. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, modules, circuits,and steps have been described above generally in terms of theirfunctionality. Whether such functionality is implemented as hardware orsoftware depends upon the particular application and design constraintsimposed on the overall system. Skilled artisans may implement thedescribed functionality in varying ways for each particular application,but such aspect decisions should not be interpreted as causing adeparture from the scope of the present disclosure.

The various illustrative logical blocks, modules, and circuits describedin connection with the aspects disclosed herein may be implemented orperformed with a general purpose processor, a DSP, an ASIC, an FPGA, orother programmable logic device, discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described herein. A general-purpose processor maybe a microprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices,e.g., a combination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration.

The methods, sequences and/or algorithms described in connection withthe aspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module may reside in random access memory (RAM), flashmemory, read-only memory (ROM), erasable programmable ROM (EPROM),electrically erasable programmable ROM (EEPROM), registers, hard disk, aremovable disk, a CD-ROM, or any other form of storage medium known inthe art. An example storage medium is coupled to the processor such thatthe processor can read information from, and write information to, thestorage medium. In the alternative, the storage medium may be integralto the processor. The processor and the storage medium may reside in anASIC. The ASIC may reside in a user terminal (e.g., UE). In thealternative, the processor and the storage medium may reside as discretecomponents in a user terminal.

In one or more example aspects, the functions described may beimplemented in hardware, software, firmware, or any combination thereof.If implemented in software, the functions may be stored on ortransmitted over as one or more instructions or code on acomputer-readable medium. Computer-readable media includes both computerstorage media and communication media including any medium thatfacilitates transfer of a computer program from one place to another. Astorage media may be any available media that can be accessed by acomputer. By way of example, and not limitation, such computer-readablemedia can comprise RAM, ROM, EEPROM, CD-ROM or other optical diskstorage, magnetic disk storage or other magnetic storage devices, or anyother medium that can be used to carry or store desired program code inthe form of instructions or data structures and that can be accessed bya computer. Also, any connection is properly termed a computer-readablemedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition of medium.Disk and disc, as used herein, includes compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk and Blu-ray discwhere disks usually reproduce data magnetically, while discs reproducedata optically with lasers. Combinations of the above should also beincluded within the scope of computer-readable media.

Other aspects are presented below. These aspects are illustrative andnot limiting.

In an aspect, a method of wireless communication performed by a firstpedestrian user equipment (PUE) includes performing a ranging operationto a set of user equipment (UEs), the set comprising at least a secondPUE; and providing ranging data to a third entity, the third entitycomprising a vehicle user equipment (VUE) or a road-side unit (RSU).

In some aspects, where the ranging data comprises location information,the location information identifying a location of the first PUE, alocation of at least one of the set of UEs, or combinations thereof.

In some aspects, the location information comprises global positioningsystem (GPS) information.

In some aspects, the third entity is a member of the set of UEs.

In some aspects, the ranging operation to the set of UEs is performedperiodically.

In some aspects, the ranging operation to the set of UEs is performed inresponse to detecting a trigger condition.

In some aspects, detecting the trigger condition comprises detectingthat the first PUE is within, or within a threshold distance from, apredetermined geographic area.

In some aspects, the predetermined geographic area is specified by thethird entity.

In some aspects, detecting the trigger condition comprises receiving arequest to perform the ranging operation.

In some aspects, the request to perform the ranging operation isreceived from the third entity, from the second PUE, or from a thirdPUE.

In some aspects, the set of UEs is selected by the third entity and therequest to perform the ranging operation comprises informationidentifying the set of UEs.

In some aspects, the set of UEs is selected by the first PUE.

In some aspects, at least one member of the set of UEs is selected basedon: a battery level of the at least one member; a battery level ofanother member of the set of UEs; a trajectory or anticipated trajectoryof the one member; a proximity or anticipated proximity of the onemember to a danger or hazard; a proximity or anticipated proximity ofthe one member to another member of the set of UEs; a level ofconfidence of a geographic location of the one member; a capability ofthe one member; a mobility status of the one member; or combinationsthereof.

In some aspects, a number of UEs in the set of UEs is based on a numberor relative density of PUEs in, or anticipated to be in, a vicinity ofthe first PUE.

In some aspects, the vicinity of the first PUE comprises an area havingthe first PUE as center and a preconfigured radius.

In some aspects, the number of UEs in the set of UEs is calculated as apreconfigured number of PUEs in the vicinity of the first PUE or apreconfigured percentage of the density of PUEs in the vicinity of thefirst PUE.

In some aspects, the preconfigured number or the preconfiguredpercentage is selected based on one or more density thresholds of thedensity of PUEs in the vicinity of the first PUE.

In an aspect, a method of wireless communication performed by a vehicleuser equipment (VUE) includes sending, to a first pedestrian userequipment (PUE), a request to perform a ranging operation to a set ofuser equipment (UEs), the set comprising at least a second PUE;receiving, from the first PUE, ranging data indicating a range from thefirst PUE to each member of the set of UEs; and determining, based onthe ranging data, an estimated position for each UE in the set of UEs.

In some aspects, where the ranging data comprises location information,the location information identifying a location of the first PUE, alocation of at least one of the set of UEs, or combinations thereof.

In some aspects, the location information comprises global positioningsystem (GPS) information.

In some aspects, the ranging data further indicates a range from thefirst PUE to the VUE.

In some aspects, the request indicates that the ranging operation to theset of UEs is to be performed periodically.

In some aspects, the request identifies a trigger condition upondetection of which the ranging operation is to be performed.

In some aspects, the trigger condition comprises detecting that thefirst PUE is within, or within a threshold distance from, apredetermined geographic area.

In some aspects, the predetermined geographic area is specified by theVUE or by a third entity.

In some aspects, the set of UEs is selected by the VUE and the requestto perform the ranging operation comprises information identifying theset of UEs.

In some aspects, the set of UEs is selected by the first PUE.

In some aspects, at least one member of the set of UEs is selected basedon: a battery level of the at least one member; a battery level ofanother member of the set of UEs; a trajectory or anticipated trajectoryof the one member; a proximity or anticipated proximity of the onemember to a danger or hazard; a proximity or anticipated proximity ofthe one member to another member of the set of UEs; a level ofconfidence of a geographic location of the one member; a capability ofthe one member; a mobility status of the one member; or combinationsthereof.

In some aspects, a number of UEs in the set of UEs is based on a numberor relative density of PUEs in, or anticipated to be in, a vicinity ofthe first PUE.

In some aspects, the vicinity of the first PUE comprises an area havingthe first PUE as center and a preconfigured radius.

In some aspects, the number of UEs in the set of UEs is calculated as apreconfigured number of PUEs in the vicinity of the first PUE or apreconfigured percentage of the density of PUEs in the vicinity of thefirst PUE.

In some aspects, the preconfigured number or the preconfiguredpercentage is selected based on one or more density thresholds of thedensity of PUEs in the vicinity of the first PUE.

In an aspect, a method of wireless communication performed by aroad-side unit (RSU) includes sending, to a first pedestrian userequipment (PUE), a request to perform a ranging operation to a set ofuser equipment (UEs), the set comprising at least a second PUE;receiving, from the first PUE, ranging data indicating a range from thefirst PUE to each member of the set of UEs; and sending, to a vehicle UE(VUE), the ranging data, an estimated position of each member of the setof UEs, or combinations thereof.

In some aspects, where the ranging data comprises location information,the location information identifying a location of the first PUE, alocation of at least one of the set of UEs, or combinations thereof.

In some aspects, the location information comprises global positioningsystem (GPS) information.

In some aspects, the ranging data further indicates a range from thefirst PUE to the RSU.

In some aspects, the request indicates that the ranging operation to theset of UEs is to be performed periodically.

In some aspects, the request identifies a trigger condition upondetection of which the ranging operation is to be performed.

In some aspects, the trigger condition comprises detecting that thefirst PUE is within, or within a threshold distance from, apredetermined geographic area.

In some aspects, the predetermined geographic area is specified by theRSU, by the VUE, or by a third entity.

In some aspects, the set of UEs is selected by the first PUE.

In some aspects, the set of UEs is selected by the RSU or by the VUE andthe request to perform the ranging operation comprises informationidentifying the set of UEs.

In some aspects, at least one member of the set of UEs is selected basedon: a battery level of the at least one member; a battery level ofanother member of the set of UEs a trajectory or anticipated trajectoryof the one member; a proximity or anticipated proximity of the onemember to a danger or hazard; a proximity or anticipated proximity ofthe one member to another member of the set of UEs; a level ofconfidence of a geographic location of the one member; a capability ofthe one member; a mobility status of the one member; a number orrelative density of PUEs in, or anticipated to be in, a vicinity of theone member; or combinations thereof.

In some aspects, a number of UEs in the set of UEs is based on a numberor relative density of PUEs in, or anticipated to be in, a vicinity ofthe first PUE.

In some aspects, the vicinity of the first PUE comprises an area havingthe first PUE as center and a preconfigured radius.

In some aspects, the number of UEs in the set of UEs is calculated as apreconfigured number of PUEs in the vicinity of the first PUE or apreconfigured percentage of the density of PUEs in the vicinity of thefirst PUE.

In some aspects, the preconfigured number or the preconfiguredpercentage is selected based on one or more density thresholds of thedensity of PUEs in the vicinity of the first PUE.

In an aspect, a pedestrian user equipment (PUE) includes a memory; atleast one transceiver; and at least one processor communicativelycoupled to the memory and the at least one transceiver, the at least oneprocessor configured to: perform a ranging operation to a set of userequipment (UEs), the set comprising at least a second PUE; and provideranging data to a third entity, the third entity comprising a vehicleuser equipment (VUE) or a road-side unit (RSU).

In some aspects, where the ranging data comprises location information,the location information identifying a location of the first PUE, alocation of at least one of the set of UEs, or combinations thereof.

In some aspects, the location information comprises global positioningsystem (GPS) information.

In some aspects, the third entity is a member of the set of UEs.

In some aspects, the ranging operation to the set of UEs is performedperiodically.

In some aspects, the ranging operation to the set of UEs is performed inresponse to detecting a trigger condition.

In some aspects, the at least one processor, when detecting the triggercondition, is configured to detect that the first PUE is within, orwithin a threshold distance from, a predetermined geographic area.

In some aspects, the predetermined geographic area is specified by thethird entity.

In some aspects, the at least one processor, when detecting the triggercondition, is configured to receive a request to perform the rangingoperation.

In some aspects, the request to perform the ranging operation isreceived from the third entity, from the second PUE, or from a thirdPUE.

In some aspects, the set of UEs is selected by the third entity and therequest to perform the ranging operation comprises informationidentifying the set of UEs.

In some aspects, the set of UEs is selected by the first PUE.

In some aspects, at least one member of the set of UEs is selected basedon: a battery level of the at least one member; a battery level ofanother member of the set of UEs; a trajectory or anticipated trajectoryof the one member; a proximity or anticipated proximity of the onemember to a danger or hazard; a proximity or anticipated proximity ofthe one member to another member of the set of UEs; a level ofconfidence of a geographic location of the one member; a capability ofthe one member; a mobility status of the one member; or combinationsthereof.

In some aspects, a number of UEs in the set of UEs is based on a numberor relative density of PUEs in, or anticipated to be in, a vicinity ofthe first PUE.

In some aspects, the vicinity of the first PUE comprises an area havingthe first PUE as center and a preconfigured radius.

In some aspects, the number of UEs in the set of UEs is calculated as apreconfigured number of PUEs in the vicinity of the first PUE or apreconfigured percentage of the density of PUEs in the vicinity of thefirst PUE.

In some aspects, the preconfigured number or the preconfiguredpercentage is selected based on one or more density thresholds of thedensity of PUEs in the vicinity of the first PUE.

In an aspect, a vehicle user equipment (VUE) includes a memory; at leastone transceiver; and at least one processor communicatively coupled tothe memory and the at least one transceiver, the at least one processorconfigured to: send, to a first pedestrian user equipment (PUE), arequest to perform a ranging operation to a set of user equipment (UEs),the set comprising at least a second PUE; receive, from the first PUE,ranging data indicating a range from the first PUE to each member of theset of UEs; and determine, based on the ranging data, an estimatedposition for each UE in the set of UEs.

In some aspects, where the ranging data comprises location information,the location information identifying a location of the first PUE, alocation of at least one of the set of UEs, or combinations thereof.

In some aspects, the location information comprises global positioningsystem (GPS) information.

In some aspects, the ranging data further indicates a range from thefirst PUE to the VUE.

In some aspects, the request indicates that the ranging operation to theset of UEs is to be performed periodically.

In some aspects, the request identifies a trigger condition upondetection of which the ranging operation is to be performed.

In some aspects, the trigger condition comprises detecting that thefirst PUE is within, or within a threshold distance from, apredetermined geographic area.

In some aspects, the predetermined geographic area is specified by theVUE or by a third entity.

In some aspects, the set of UEs is selected by the VUE and the requestto perform the ranging operation comprises information identifying theset of UEs.

In some aspects, the set of UEs is selected by the first PUE.

In some aspects, at least one member of the set of UEs is selected basedon: a battery level of the at least one member; a battery level ofanother member of the set of UEs; a trajectory or anticipated trajectoryof the one member; a proximity or anticipated proximity of the onemember to a danger or hazard; a proximity or anticipated proximity ofthe one member to another member of the set of UEs; a level ofconfidence of a geographic location of the one member; a capability ofthe one member; a mobility status of the one member; or combinationsthereof.

In some aspects, a number of UEs in the set of UEs is based on a numberor relative density of PUEs in, or anticipated to be in, a vicinity ofthe first PUE.

In some aspects, the vicinity of the first PUE comprises an area havingthe first PUE as center and a preconfigured radius.

In some aspects, the number of UEs in the set of UEs is calculated as apreconfigured number of PUEs in the vicinity of the first PUE or apreconfigured percentage of the density of PUEs in the vicinity of thefirst PUE.

In some aspects, the preconfigured number or the preconfiguredpercentage is selected based on one or more density thresholds of thedensity of PUEs in the vicinity of the first PUE.

In an aspect, a road-side unit (RSU) includes a memory; at least onetransceiver; and at least one processor communicatively coupled to thememory and the at least one transceiver, the at least one processorconfigured to: send, to a first pedestrian user equipment (PUE), arequest to perform a ranging operation to a set of user equipment (UEs),the set comprising at least a second PUE; receive, from the first PUE,ranging data indicating a range from the first PUE to each member of theset of UEs; and send, to a vehicle UE (VUE), the ranging data, anestimated position of each member of the set of UEs, or combinationsthereof.

In some aspects, where the ranging data comprises location information,the location information identifying a location of the first PUE, alocation of at least one of the set of UEs, or combinations thereof.

In some aspects, the location information comprises global positioningsystem (GPS) information.

In some aspects, the ranging data further indicates a range from thefirst PUE to the RSU.

In some aspects, the request indicates that the ranging operation to theset of UEs is to be performed periodically.

In some aspects, the request identifies a trigger condition upondetection of which the ranging operation is to be performed.

In some aspects, the trigger condition comprises detecting that thefirst PUE is within, or within a threshold distance from, apredetermined geographic area.

In some aspects, the predetermined geographic area is specified by theRSU, by the VUE, or by a third entity.

In some aspects, the set of UEs is selected by the first PUE.

In some aspects, the set of UEs is selected by the RSU or by the VUE andthe request to perform the ranging operation comprises informationidentifying the set of UEs.

In some aspects, at least one member of the set of UEs is selected basedon: a battery level of the at least one member; a battery level ofanother member of the set of UEs a trajectory or anticipated trajectoryof the one member; a proximity or anticipated proximity of the onemember to a danger or hazard; a proximity or anticipated proximity ofthe one member to another member of the set of UEs; a level ofconfidence of a geographic location of the one member; a capability ofthe one member; a mobility status of the one member; a number orrelative density of PUEs in, or anticipated to be in, a vicinity of theone member; or combinations thereof.

In some aspects, a number of UEs in the set of UEs is based on a numberor relative density of PUEs in, or anticipated to be in, a vicinity ofthe first PUE.

In some aspects, the vicinity of the first PUE comprises an area havingthe first PUE as center and a preconfigured radius.

In some aspects, the number of UEs in the set of UEs is calculated as apreconfigured number of PUEs in the vicinity of the first PUE or apreconfigured percentage of the density of PUEs in the vicinity of thefirst PUE.

In some aspects, the preconfigured number or the preconfiguredpercentage is selected based on one or more density thresholds of thedensity of PUEs in the vicinity of the first PUE.

In an aspect, a pedestrian user equipment (PUE) includes means forperforming a ranging operation to a set of user equipment (UEs), the setcomprising at least a second PUE; and means for providing ranging datato a third entity, the third entity comprising a vehicle user equipment(VUE) or a road-side unit (RSU).

In an aspect, a vehicle user equipment (VUE) includes means for sending,to a first pedestrian user equipment (PUE), a request to perform aranging operation to a set of user equipment (UEs), the set comprisingat least a second PUE; means for receiving, from the first PUE, rangingdata indicating a range from the first PUE to each member of the set ofUEs; and means for determining, based on the ranging data, an estimatedposition for each UE in the set of UEs.

In an aspect, a road-side unit (RSU) includes means for sending, to afirst pedestrian user equipment (PUE), a request to perform a rangingoperation to a set of user equipment (UEs), the set comprising at leasta second PUE; means for receiving, from the first PUE, ranging dataindicating a range from the first PUE to each member of the set of UEs;and means for sending, to a vehicle UE (VUE), the ranging data, anestimated position of each member of the set of UEs, or combinationsthereof.

In an aspect, a non-transitory computer-readable medium storing a set ofinstructions, the set of instructions comprising one or moreinstructions that, when executed by one or more processors of apedestrian user equipment (PUE), cause the PUE to: perform a rangingoperation to a set of user equipment (UEs), the set comprising at leasta second PUE; and provide ranging data to a third entity, the thirdentity comprising a vehicle user equipment (VUE) or a road-side unit(RSU).

In an aspect, a non-transitory computer-readable medium storing a set ofinstructions, the set of instructions comprising one or moreinstructions that, when executed by one or more processors of a vehicleuser equipment (VUE), cause the VUE to: send, to a first pedestrian userequipment (PUE), a request to perform a ranging operation to a set ofuser equipment (UEs), the set comprising at least a second PUE; receive,from the first PUE, ranging data indicating a range from the first PUEto each member of the set of UEs; and determine, based on the rangingdata, an estimated position for each UE in the set of UEs.

In an aspect, a non-transitory computer-readable medium storing a set ofinstructions, the set of instructions comprising one or moreinstructions that, when executed by one or more processors of anroad-side unit (RSU), cause the RSU to: send, to a first pedestrian userequipment (PUE), a request to perform a ranging operation to a set ofuser equipment (UEs), the set comprising at least a second PUE; receive,from the first PUE, ranging data indicating a range from the first PUEto each member of the set of UEs; and send, to a vehicle UE (VUE), theranging data, an estimated position of each member of the set of UEs, orcombinations thereof.

While the foregoing disclosure shows illustrative aspects of thedisclosure, it should be noted that various changes and modificationscould be made herein without departing from the scope of the disclosureas defined by the appended claims. The functions, steps and/or actionsof the method claims in accordance with the aspects of the disclosuredescribed herein need not be performed in any particular order.Furthermore, although elements of the disclosure may be described orclaimed in the singular, the plural is contemplated unless limitation tothe singular is explicitly stated.

What is claimed is:
 1. A vehicle user equipment (VUE), comprising: amemory; at least one transceiver; and at least one processorcommunicatively coupled to the memory and the at least one transceiver,the at least one processor configured to: send, to a first pedestrianuser equipment (PUE), a request to perform a ranging operation to a setof user equipment (UEs), the set of UEs comprising at least a secondPUE; receive, from the first PUE, ranging data indicating a range fromthe first PUE to each member of the set of UEs; and determine, based onthe ranging data, an estimated position for each UE in the set of UEs.2. The VUE of claim 1, where the ranging data comprises locationinformation, the location information identifying a location of thefirst PUE, a location of at least one of the set of UEs, a range fromthe first PUE to the VUE, or combinations thereof.
 3. The VUE of claim1, wherein the request indicates that the ranging operation to the setof UEs is to be performed periodically, identifies a trigger conditionupon detection of which the ranging operation is to be performed, orcombinations thereof.
 4. The VUE of claim 3, wherein the triggercondition comprises detecting that the first PUE is within, or within athreshold distance from, a predetermined geographic area.
 5. The VUE ofclaim 1, wherein at least one member of the set of UEs is selected basedon: a battery level of the at least one member; a battery level ofanother member of the set of UEs; a trajectory or anticipated trajectoryof the one member; a proximity or anticipated proximity of the onemember to a danger or hazard; a proximity or anticipated proximity ofthe one member to another member of the set of UEs; a level ofconfidence of a geographic location of the one member; a capability ofthe one member; a mobility status of the one member; or combinationsthereof.
 6. A road-side unit (RSU), comprising: a memory; at least onetransceiver; and at least one processor communicatively coupled to thememory and the at least one transceiver, the at least one processorconfigured to: send, to a first pedestrian user equipment (PUE), arequest to perform a ranging operation to a set of user equipment (UEs),the set of UEs comprising at least a second PUE; receive, from the firstPUE, ranging data indicating a range from the first PUE to each memberof the set of UEs; and send, to a vehicle UE (VUE), the ranging data, anestimated position of each member of the set of UEs, or combinationsthereof.
 7. The RSU of claim 6, where the ranging data compriseslocation information, the location information identifying a location ofthe first PUE, a location of at least one of the set of UEs, a rangefrom the first PUE to the RSU, or combinations thereof.
 8. The RSU ofclaim 6, wherein the request indicates that the ranging operation to theset of UEs is to be performed periodically, identifies a triggercondition upon detection of which the ranging operation is to beperformed, or combinations thereof.
 9. The RSU of claim 8, wherein thetrigger condition comprises detecting that the first PUE is within, orwithin a threshold distance from, a predetermined geographic area. 10.The RSU of claim 6, wherein at least one member of the set of UEs isselected based on: a battery level of the at least one member; a batterylevel of another member of the set of UEs a trajectory or anticipatedtrajectory of the one member; a proximity or anticipated proximity ofthe one member to a danger or hazard; a proximity or anticipatedproximity of the one member to another member of the set of UEs; a levelof confidence of a geographic location of the one member; a capabilityof the one member; a mobility status of the one member; a number orrelative density of PUEs in, or anticipated to be in, a vicinity of theone member; or combinations thereof.
 11. The RSU of claim 6, wherein anumber of UEs in the set of UEs is based on a number or relative densityof PUEs in, or anticipated to be in, a vicinity of the first PUE. 12.The RSU of claim 11, wherein the vicinity of the first PUE comprises anarea having the first PUE as center and a preconfigured radius.
 13. Amethod of wireless communication performed by a first user equipment(UE), the method comprising: sending, to a second UE, a request toperform a ranging operation to a set of user equipment (UEs), the set ofUEs comprising at least a pedestrian UE (PUE); receiving, from thesecond UE, ranging data indicating a range from the second UE to eachmember of the set of UEs; and determining, based on the ranging data, anestimated position for each UE in the set of UEs.
 14. The method ofclaim 13, wherein at least one of the first UE and the second UEcomprises a vehicle UE (VUE) or a PUE.
 15. The method of claim 13, wherethe ranging data comprises location information, the locationinformation identifying a location of the second UE, a location of atleast one of the set of UEs, a range from the second UE to the first UE,or combinations thereof.
 16. The method of claim 13, wherein the requestindicates that the ranging operation to the set of UEs is to beperformed periodically.
 17. The method of claim 13, wherein the requestidentifies a trigger condition upon detection of which the rangingoperation is to be performed.
 18. The method of claim 17, wherein thetrigger condition comprises detecting that the second UE is within, orwithin a threshold distance from, a predetermined geographic area. 19.The method of claim 13, wherein the set of UEs is selected by the firstUE and wherein the request to perform the ranging operation comprisesinformation identifying the set of UEs.
 20. The method of claim 13,wherein the set of UEs is selected by the second UE.
 21. The method ofclaim 13, wherein at least one member of the set of UEs is selectedbased on: a battery level of the at least one member; a battery level ofanother member of the set of UEs; a trajectory or anticipated trajectoryof the one member; a proximity or anticipated proximity of the onemember to a danger or hazard; a proximity or anticipated proximity ofthe one member to another member of the set of UEs; a level ofconfidence of a geographic location of the one member; a capability ofthe one member; a mobility status of the one member; or combinationsthereof.
 22. The method of claim 13, wherein a number of UEs in the setof UEs is based on a number or relative density of PUEs in, oranticipated to be in, a vicinity of the second UE.
 23. The method ofclaim 22, wherein the vicinity of the second UE comprises an area havingthe second UE as center and a preconfigured radius.
 24. The method ofclaim 22, wherein the number of UEs in the set of UEs is calculated as apreconfigured number of PUEs in the vicinity of the second UE or apreconfigured percentage of the relative density of PUEs in the vicinityof the second UE.
 25. The method of claim 24, wherein the preconfigurednumber of PUEs in the vicinity of the second UE or a preconfiguredpercentage of the relative density of PUEs in the vicinity of the secondUE is selected based on one or more density thresholds of the relativedensity of PUEs in the vicinity of the second UE.